Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Mnyb wrote: The trend I was referring to with my blanket dismissal of NOS DAC was the ones completely without any filter, this was very popular as DIY for while so popular that it seems to be the norm :-/ That's it in a nutshell. Most recent work with NOS DACs has centered around the Philips TDA 1541 as a more-or-less stand alone DAC with no or minimal to vestigial low pass filtering. If you study its history it was never really intended by its developers to be used that way. Information about how the TDA 1541 was supposed to used was discussed in the early days of digital audio (1981-1983) by professional magazines like as EDN and EE Times (if they existed them and if they didn't their forebearers), but issues of those periodicals that old seem to be lost to posterity. There may be relevant Philips Application notes, but I can't find them either. The TDA 1541 chip was originally designed to be a component of an oversampled DAC, most significantly to be followed by a digital filter chip such as the SAA7030 and its sequels. One fact that I haven't seen is references to what used to be called Aperture Effect which is the reason why the output of many DAC chips have an unexpected (to many) droop at high frequencies. This issue is discussed in the context of data acquisition here: http://www.cypress.com/?docID=45630. When used all by itself the output of a TDA 1541 chip is going to have that HF-drooping frequency response that is shown in the Cyprus Semiconductor reference in figure 1. The digital filter chips such as the SAA7030 that it was supposed to be used with such as the contained corrections for this that were in the day called . It is as simple as that - the TDA 1541 was never intended to be used without some kind of Aperture Correction, and if you don't provide it, its going to sound a little soft compared to an accurate DAC. There are other potential bad consequences to not having an appropriate reconstruction filter following the DAC such as IM in following stages of amplification due to the fairly large amounts of HF noise that is not filtered out like it should be. The noise itself is 22 KHz and likely to not be heard by many if anybody. The IM doesn't always happen to an audible degree, but I'm sure given the relatively high amplitude of this noise it does happen some times. I suspect that there are even people who like their music with a little aharmonic nonlinear distortion spurious responses tossed in. arnyk's Profile: http://forums.slimdevices.com/member.php?userid=64365 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Wombat;692608 Wrote: Hi Mnyb i just realized today that your signature must have changed lately. Isn´t it? Using new Meridian DSP is like cheating! No wonder you don´t hear a difference with transports. These babies simply seem to work :) Congrats for the purchase! Yea I hesitated for years before I did it they are are not perfect but they are done right, makes other hifi looks like steam engines (nice and complicated and well put together but why ? ) They are a good proof of concept how hifi and home theater should be done . A pity they are the only game in town :-/ if others get it (including other brands and audiophiles ) this kind of solution would go down in price and improve at the same time . I'm a tech nerd :) I do like the underlying architecture of this system, I wish meridian could license their speaker-link MHR connection . Or if someone could make a conection standard for digital active speakers. I have used the processor much longer than the speakers. It all started when DVDA was hot , there where not many that offered 6ch 24/96k digital link from the player to the processor (now with hdmi everyone has it ) . The benefit of 24/96 may be questionable , but using an analog DA-AD-DA route via a traditional HT receiver will blow even that small chance to improvement away . This system is source transparent even trough the xover and sound degradation does not start until the the signal Reach the DAC and amp for that speaker driver . Strictly I could have bought some nice analog active speakers and maybe get better sound. But the Meridian solution is so neat just cat5 cables to the speakers -- Mnyb Main hifi: Touch + CIA PS +MeridianG68J MeridianHD621 MeridianG98DH 2 x MeridianDSP5200 MeridianDSP5200HC 2 xMeridianDSP3100 +Rel Stadium 3 sub. Bedroom/Office: Boom Kitchen: Touch + powered Fostex PM0.4 Misc use: Radio (with battery) iPad 64gB wifi +3g with iPengHD SqueezePad (in storage SB3, reciever ,controller ) Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Mnyb;692643 Wrote: Strictly I could have bought some nice analog active speakers and maybe get better sound. But the Meridian solution is so neat just cat5 cables to the speakers Although personally I like ATC (not just the sound but the ethos) I heard Meridian DSP5200 a few years ago at a show and I thought they sounded great and are, as you say, an extremely neat and modern solution. Good choice IMO. I heard the M80 at the same show and I didn't like it, TBH. But I wouldn't mind a listen of the DSP3200 plus DSW sub...! Darren -- darrenyeats http://www.amazon.co.uk/gp/richpub/listmania/byauthor/A3H57URKQB8AQO/ref=cm_pdp_content_listmania/203-7606506-5721503. SB Touch darrenyeats's Profile: http://forums.slimdevices.com/member.php?userid=10799 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
darrenyeats;692658 Wrote: Although personally I like ATC (not just the sound but the ethos) I heard Meridian DSP5200 a few years ago at a show and I thought they sounded great and are, as you say, an extremely neat and modern solution. Good choice IMO. Active speakers have a lot of advantages and of course Meridian have their own unique take even on the active architecture. I heard the M80 at the same show and I didn't like it, TBH. But I wouldn't mind a listen of the DSP3200 plus DSW sub...! Darren Yea ATC been around since the 70's and Meridians first DSP speaker arrived 1990 22 years ago ? And no one else picked it up ? :-/ I may not repeat what I think of the so called design of modern high end. -- Mnyb Main hifi: Touch + CIA PS +MeridianG68J MeridianHD621 MeridianG98DH 2 x MeridianDSP5200 MeridianDSP5200HC 2 xMeridianDSP3100 +Rel Stadium 3 sub. Bedroom/Office: Boom Kitchen: Touch + powered Fostex PM0.4 Misc use: Radio (with battery) iPad 64gB wifi +3g with iPengHD SqueezePad (in storage SB3, reciever ,controller ) Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
my klein and hummel 0300d with the c28 has loads of room correction options..of course they are also digital -- TheOctavist VortexboxSBT(stock)Forssell MDAC-2Klein and Hummell 0300D Sota Sapphire/Lyra KleosBespoke Valve Phono StageMastersound Due VentiLink Audio K100 TheOctavist's Profile: http://forums.slimdevices.com/member.php?userid=52700 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
KH is a pro monitor speaker very neat design, the xover is analog thou, transformer coupled analog input ? But you are using an old forsell DAC not the KH built in DAC ? If you want to use the digital input how do you practically do things like adding a subwoofer and how do you do hometheater , using the analog inputs ? Or a pro mixing console or software and multi channel sound card ? The 300 seems to be a control desk monitor do they work fine on stands used as normal speakers, they got one very good feat, centre channel would be identical . I reckon KH deemed the home use Market hopeless :-/ not any models adapted to that. -- Mnyb Main hifi: Touch + CIA PS +MeridianG68J MeridianHD621 MeridianG98DH 2 x MeridianDSP5200 MeridianDSP5200HC 2 xMeridianDSP3100 +Rel Stadium 3 sub. Bedroom/Office: Boom Kitchen: Touch + powered Fostex PM0.4 Misc use: Radio (with battery) iPad 64gB wifi +3g with iPengHD SqueezePad (in storage SB3, reciever ,controller ) Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
how do one controll the volume of a pair of digitally connected KH ? Example in my meridian system volume controll is in the speakers and the volume information is passed on from the processor in the speaker link . -- Mnyb Main hifi: Touch + CIA PS +MeridianG68J MeridianHD621 MeridianG98DH 2 x MeridianDSP5200 MeridianDSP5200HC 2 xMeridianDSP3100 +Rel Stadium 3 sub. Bedroom/Office: Boom Kitchen: Touch + powered Fostex PM0.4 Misc use: Radio (with battery) iPad 64gB wifi +3g with iPengHD SqueezePad (in storage SB3, reciever ,controller ) Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Hi Mnyb i just realized today that your signature must have changed lately. Isn´t it? Using new Meridian DSP is like cheating! No wonder you don´t hear a difference with transports. These babies simply seem to work :) Congrats for the purchase! -- Wombat Transporter (modded) - RG142 - Avantgarde Acoustic based 500VA monoblocks - Sommer SPK240 - self-made speakers Wombat's Profile: http://forums.slimdevices.com/member.php?userid=4113 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Archimago;692235 Wrote: Thanks for sharing your experience with DAC's John! Over the years I have played with a cheap DIY 4-chip TDA1543 design similar to the stuff on eBay as well as a more expensive Mhdt Constantine (TDA1545 I think). Can't say I was enamoured with the sound... I found the highs a bit too rolled off for my taste so happily went back to the Transporter sound. Wondering if there was a commercially available NOS DAC you think represents a good design. I don't have time anymore to fool around with DIY's. As for the slow roll-off filter, any opinions on the Transporter's AK4396 slow-roll vs. standard filter? If I were going to buy a NOS DAC today I would get the Audio-gd DAC-19, it uses a pair of 1704K chips (my personal favorites). It also does what I do, it implements its own digital filters in an FPGA (strangely enough exactly the same FPGA chip I use in my latest DAC). You can also set it to NOS mode if you desire. Its not the cheapest DAC nor the most expensive. I think it does a good job all around (except for maybe the USB input). I have not had a change to listen to the Transporter's slow rolloff mode so I can't comment on that. John S. -- JohnSwenson JohnSwenson's Profile: http://forums.slimdevices.com/member.php?userid=5974 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Phil Leigh;692199 Wrote: So John, are you saying that on 44.1 material you prefer a NOS with a good analogue filter set for 22Khz vs an ASRC DAC running internally at 384 or 768 with an appropriate digital filter? Just curious. That dirt you refer to is exactly what I don't like about all of the NOS DAC's I've heard. Of course this doesn't mean ALL NOS DAC's are empirically bad... simply that I personally haven't heard what I consider to be a good one. Interesting about the heat phenomena. The heat must be causing the Johnson noise to rise inside the DAC, no:? - maybe the noise is having a dithering effect? regards Phil My preference is a DAC which uses properly implemented digital filters, unfortunately these are rare. The NOS DAC and software approach is a way to get around trying to find hardware with good digital filters. By doing the oversampling in software you have FAR more flexibility in playing with different filter parameters. For my own DACs I've spent years going back and forth between NOS and digital filters. A NOS DAC with several poles of analog filtering can sound quite good. But the best is still digital filtering done right. Of course that takes significant digital horse power, which means you have to be very carfeful that the noise from the filter doesn't make it into the clock circuits, DAC chips and analog circuits. That takes very careful grounding and PS design, none of which comes cheap. I personally do not like ASRCs. I have not heard a single one that I really like. Of course it may not be the ASRC per se. I expect part of it might be the interaction of the imperfect digital filters in both the ASRC and the DAC chip interacting with each other. On the HOT DAC I suspect its due to internal PS noise. As the chips get hotter the FETs in the circuits get higher resistance, which slows them down (RC goes up) so the peak current from each switching goes down, thus less noise on power and ground traces in the chip and package. As the temperature goes up at some point things get so slow it stops working, you don't want to go that far! John S. -- JohnSwenson JohnSwenson's Profile: http://forums.slimdevices.com/member.php?userid=5974 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
The trend I was referring to with my blanket dismissal of NOS DAC was the ones completely without any filter, this was very popular as DIY for while so popular that it seems to be the norm :-/ -- Mnyb Main hifi: Touch + CIA PS +MeridianG68J MeridianHD621 MeridianG98DH 2 x MeridianDSP5200 MeridianDSP5200HC 2 xMeridianDSP3100 +Rel Stadium 3 sub. Bedroom/Office: Boom Kitchen: Touch + powered Fostex PM0.4 Misc use: Radio (with battery) iPad 64gB wifi +3g with iPengHD SqueezePad (in storage SB3, reciever ,controller ) Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
I have a lot to say on this subject, but its too much for one post so I'll start with the topic of NOS DACs since its being discussed right now. First off a bit of background, I have been building DACs for quite a few years, I have built at least 30 different DACs with many different DAC chips, filters, output stages etc. I have tried hard to come up with at least some correlations between differences in what I have been building and what I have heard, this hasn't been easy, there are so many variables it's hard to narrow things down. And yes I found there ARE differences in sound, they do not all sound the same. I have done quite a few blind tests with other people listening, they were at least single blind, sometimes double blind. The blind tests do prove that there are differences, but preferences as to what people preferred went all over the place. So the following is going to be my own personal preferences, which are certain to be different than other people. Before going into details of my NOS experience let me say that I am an electronics engineer, I am well versed in sampling theory and have a moderate acquaintance with DSP, but by no means the worlds greatest living expert. When I first started Building DACs I was firmly in the oversampling is a great thing camp, it radically improves upon the old style brickwall analog filter etc. Then I heard about NOS DACs and decided to build a couple and see what they sound like. I was sure it was going to be terrible. But low and behold that is not what happened. I found the sound was significantly improved in some areas and significantly degraded in others. This was a big surprise, I was not expecting the improvement at all. At this point I had no clue WHY it sounded better. I tried several NOS DAC designs of my own and several from other people. What I found was that a lot of the NOS DAC designs out there were seriously flawed in many ways, it was obvious the people designing them really didn't know what they were doing. Frequently I could make them sound much better by some simple changes. Even with some of these bad design choices they all definitely have a NOS sound. To me the improvement part is an increase in subtle detail, being able to hear subtle details of the acoustic environment, being able to hear subtle nuances in performance that purvey emotional content better. At the same time, the sound is dirty, its rough around the edges. When you go back to oversampling it sounds much cleaner, but also flat and boring in comparison. My supposition is that the people that like NOS DACs are willing to ignore the bad parts in order to gain the good parts. It might also have to do with age, young people with good hearing may be bothered much more by the dirty sound (presumably the infamous aliasing). I then spent a couple years trying to find out why the NOS DACs sound better. I won't go into the full journey here, but what I eventually concluded was that it was the digital filters themselves getting in the way. I could build my own digital filters that kept the good qualities of the NOS sound but without the dirt. I wasn't doing anything special with my filters, just a good proper implementation in an FPGA. The only thing I can think of as to why the commercial ones do not sound so good is that they are NOT properly implemented. In order to properly do a brickwall filter for 44.1 takes a fair amount of hardware resources, my guess is that the manufacturers are cutting corners to save money. They are doing just barely enough to get decent numbers in the data sheets. In particular I'm leaning towards the practice of cascading several small filters rather than using one properly implemented large filter. Looking at data sheet plots of filter performance you can frequently see this cascading of filters. An interesting occurrence happened early in my DAC quest (before my first NOS DAC) I had an inexpensive DVD player and decided to see if I could get it to sound better. I did a number of analog and PS improvements which improved things significantly, but I also noticed that the DAC chip had a slow rolloff filter setting as well as the default brickwall filter. So I built a little board that let me reprogram the registers in the DAC chip so I could set the filter type. I found that I liked the slow rolloff much better. In blind tests most people liked the slow better, but several hated it. Looking at the data sheet plots I found that the slow filter was implemented as a single filter but the brickwall was three cascaded filters. I have done similar tests with many other DAC chips and with my own digital filters and its turning out to be a fairly decent correlation that the biggest impact is not the filter function itself but if its implemented as cascaded filters. Filter functions DO make a difference, but if they are all implemented as cascaded filters they all don't sound so great. With filters implemented as single proper filters (enough
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
So John, are you saying that on 44.1 material you prefer a NOS with a good analogue filter set for 22Khz vs an ASRC DAC running internally at 384 or 768 with an appropriate digital filter? Just curious. That dirt you refer to is exactly what I don't like about all of the NOS DAC's I've heard. Of course this doesn't mean ALL NOS DAC's are empirically bad... simply that I personally haven't heard what I consider to be a good one. Interesting about the heat phenomena. The heat must be causing the Johnson noise to rise inside the DAC, no:? - maybe the noise is having a dithering effect? regards Phil -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal... Touch(wired/W7)+Teddy Pardo PSU - Audiolense 3.3/2.0+INGUZ DRC - MF M1 DAC - Linn 5103 - full Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Pekin Tuner, Townsend Supertweeters,VdH Toslink,Kimber 8TC Speaker Chord Signature Plus Interconnect cables Stax4070+SRM7/II phones Kitchen Boom, Outdoors: SB Radio, Harmony One remote for everything. Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Thanks for sharing your experience with DAC's John! Over the years I have played with a cheap DIY 4-chip TDA1543 design similar to the stuff on eBay as well as a more expensive Mhdt Constantine (TDA1545 I think). Can't say I was enamoured with the sound... I found the highs a bit too rolled off for my taste so happily went back to the Transporter sound. Wondering if there was a commercially available NOS DAC you think represents a good design. I don't have time anymore to fool around with DIY's. As for the slow roll-off filter, any opinions on the Transporter's AK4396 slow-roll vs. standard filter? -- Archimago Archimago's Profile: http://forums.slimdevices.com/member.php?userid=2207 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
JohnSwenson;692188 Wrote: This brings up the issue of software upsampling and NOS DACs. First off NOS does not mean no filter, just not a digital filter, you can still put an analog filter on a NOS DAC. If the builtin digital filters are the problem, it seems that a good NOS DAC playing upsampled files that were generated with a properly implemented software filter should provide good sound. And my experience is that indeed it does, especially if you put a 2 or 3 pole analog filter after the NOS DAC to get rid of residual high frequency noise. Note this has to be a GOOD NOS DAC, not one of those cheap 16 bit ones from people that have no clue what they are doing. There are a lot of people that are doing software upsampling and feeding the results into soundcards and external DACs that I think are trying to do the same sort of thing, but the data is still going through the compromised digital filter in the DAC chip. It would be much better if they fed it through a good NOS DAC. John this is fascinating stuff, but the terminology is getting confusing to me. NOS literally stands for non oversampling (?) - but tends to be associated with either no filter or analogue output filter. Forgive my ignorance but how do upsampled files that were generated with a properly implemented software filter differ from the up/oversampling which would go on in an ordinary OS dac? It seems to me that you clearly have both oversampling and a digital filter here- your just doing it in software. For the sake of simplifying Inguz all my files are (courtesy of Phil's tweak) upsampled by sox to 96 kHz before streaming to my dac. Is this what you have in mind? I can't see how you can go beyond 96kHz via a squeezebox If the processing power in the dac is the limiting factor I see why it might be better to finesse this in software. I hope I am not making a fool of myself by I can't see how this differs in principle from the classic OS dac with a final analog filter to remove images above half the oversampling frequency. Would this be NOS in the sense that Kusunoki meant it http://www.sakurasystems.com/articles/Kusunoki.html Presumably with will only work with a multi bit dac this natively works at the upsampled frequency not a delta sigma one as those will presumably inevitably have their own filters. [I fear I am betraying my ignorance but I have never been able to grasp the difference between upsampling and oversampling] -- adamdea adamdea's Profile: http://forums.slimdevices.com/member.php?userid=37603 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
evdplancke;690903 Wrote: 2) fanatics of NOS DAC will benefit from hires even up to 384khz because the higher the fs, the flatter the sin x/x lowpass in audible frequency band... Then what about a NOS DAC without output filtering (using ear natural lowpass filtering): this would get rid of pre-ringing filtering artefacts. Combined with ultra hires, wouldn't it be close to the perfect sound? There is an element of truth in it if you are determined to see a point in NOS dacs, but it is still utterly illogical. All you are saying is that NOS dacs will work better if oversampling (in the sense of increasing the sample rate from the native rate of the data being decoded) is unnecessary. Oversampling is unnecessary if the native rate of the data is already at the rate you would have oversampled to. A nos dac with data fs = 192k will presumably bahabve in the audible band just like a 4x oversampling dac weith 44.1 data but no filter. So now with no reconstrction filter and Fs = 192k or whatever we only have to aorry about images at 96Khz plus. This does not remove the problem that somw downstream electronics will still not like the spuria at 96Khz. I am also not sure whether the combination of intermoudation distortion and imaging which causes NOS dacs to have such a poor noise floor at 44.1 will also affects them at fs =192 or whatver. Anyway there is now no reason *not* to have a reconstruction filter. (when i say reason I mean the spurous reason which justified nos dacs in the first place). Even if there are audible pre-ringing artefacts at fs=44.1 surely even an audiophile wouldn't think they existed at fs=192k (which you will note is Bruno Putzeys point about apodising filters) . So at higher sampling rates the nos dac makes no sense whatsoever -- adamdea adamdea's Profile: http://forums.slimdevices.com/member.php?userid=37603 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
NOS DACS are a ruse. http://www.head-fi.org/t/437340/any-benefits-from-having-a-higher-sample-rate/15#post_5905139 -- TheOctavist VortexboxSBT(stock)Forssell MDAC-2Klein and Hummell 0300D Sota Sapphire/Lyra KleosBespoke Valve Phono StageMastersound Due VentiLink Audio K100 TheOctavist's Profile: http://forums.slimdevices.com/member.php?userid=52700 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
TheOctavist;691020 Wrote: NOS DACS are a ruse. http://www.head-fi.org/t/437340/any-benefits-from-having-a-higher-sample-rate/15#post_5905139 But they do sound different ;) Amazing if the punter finds that all dac's sound's similar and then finds the nos dac very different . how on earth do you get to logic defying conclusion that the NOS dac is an improvement ??? -- Mnyb Main hifi: Touch + CIA PS +MeridianG68J MeridianHD621 MeridianG98DH 2 x MeridianDSP5200 MeridianDSP5200HC 2 xMeridianDSP3100 +Rel Stadium 3 sub. Bedroom/Office: Boom Kitchen: Touch + powered Fostex PM0.4 Misc use: Radio (with battery) iPad 64gB wifi +3g with iPengHD SqueezePad (in storage SB3, reciever ,controller ) Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Thanks for your very interesting post. So we can conclude from there: 1) there is a benefit of using 48khz instead of 44,1khz because of the reconstruction filter 2) fanatics of NOS DAC will benefit from hires even up to 384khz because the higher the fs, the flatter the sin x/x lowpass in audible frequency band... Then what about a NOS DAC without output filtering (using ear natural lowpass filtering): this would get rid of pre-ringing filtering artefacts. Combined with ultra hires, wouldn't it be close to the perfect sound? -- evdplancke evdplancke's Profile: http://forums.slimdevices.com/member.php?userid=43147 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
evdplancke;690903 Wrote: Thanks for your very interesting post. So we can conclude from there: 1) there is a benefit of using 48khz instead of 44,1khz because of the reconstruction filter 2) fanatics of NOS DAC will benefit from hires even up to 384khz because the higher the fs, the flatter the sin x/x lowpass in audible frequency band... Then what about a NOS DAC without output filtering (using ear natural lowpass filtering): this would get rid of pre-ringing filtering artefacts. Combined with ultra hires, wouldn't it be close to the perfect sound? To 1) there is still this theoretical filterproblem that even in real-world isn´t. It is only a problem for many because it is there theoretical. Can you hear the different filters acting around 20kHz? To 2) i never listened to a NOS DAC and many seem to love it while others find even the best NOS DAC sounds horrible. The music it spits out without sinc filter is indeed horrible to measure and for sure will benefit of higher sampling frequencies most. Now this is a case to wonder, even when the output is technicaly speaking pretty less precise it still may be sounding fantastic to some. -- Wombat Transporter (modded) - RG142 - Avantgarde Acoustic based 500VA monoblocks - Sommer SPK240 - self-made speakers Wombat's Profile: http://forums.slimdevices.com/member.php?userid=4113 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
evdplancke;690903 Wrote: Thanks for your very interesting post. So we can conclude from there: 1) there is a benefit of using 48khz instead of 44,1khz because of the reconstruction filter 2) fanatics of NOS DAC will benefit from hires even up to 384khz because the higher the fs, the flatter the sin x/x lowpass in audible frequency band... Then what about a NOS DAC without output filtering (using ear natural lowpass filtering): this would get rid of pre-ringing filtering artefacts. Combined with ultra hires, wouldn't it be close to the perfect sound? 1) IME Only very few people can hear the small difference between 44.1 and 48. I used to be able to 15 years ago when DAT machines were popular but I can't anymore. Even then it was a tiny tiny difference on my top end Sony and I couldn't in all honesty say it was really down to the filtering. It might just have been a better DAC. 2) All of the NOS DAC's I've heard sound uniformly dreadful in the upper mid and top end to me YMMVof course. -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal... Touch(wired/W7)+Teddy Pardo PSU - Audiolense 3.3/2.0+INGUZ DRC - MF M1 DAC - Linn 5103 - full Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Pekin Tuner, Townsend Supertweeters,VdH Toslink,Kimber 8TC Speaker Chord Signature Plus Interconnect cables Stax4070+SRM7/II phones Kitchen Boom, Outdoors: SB Radio, Harmony One remote for everything. Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Wow, great post Octavist! -- Archimago Archimago's Profile: http://forums.slimdevices.com/member.php?userid=2207 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
wow thanks very much- this is really interesting. Please say thank you from me. I shall have a good read and properly digest it before asked any dumb questions back. -- adamdea adamdea's Profile: http://forums.slimdevices.com/member.php?userid=37603 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
From Mr. Putzeys. Nope. If there is absolutely no content above a certain f, any sampling rate of 2*f or over will reconstruct the exact same signal. Sampling theory proves that a correctly executed (=filtered before and after) sampling conversion system is indistinguishable from a lowpass filter. And a lowpass filter is indistinguishable from nothing at all if the signal has nothing for the lowpass filter to remove. The latter assumes linear phase lowpass filters of course, but those are standard in AD/DA these days. Needless to say, when there is content above 20kHz the question gets hairier. a. In formal (double blind) trials, no results have yet been reported of listeners able to distinguish between a high sampling rate audio signal and same with a lowpass filter inserted. Note that the ear is not a linear device. That is to say, you can't draw conclusions regarding audibility of HF spectral content based on audibility of single tone stimuli. For instance, quite a few people whose hearing ostensibly stops at 10k are able to detect the insertion of a 15kHz lowpass filter. But it does appear that 20kHz is roughly where it ends. b, c. I do mean roughly. If you make the filter very sharp and let it cut off right at 20kHz it can become ridiculously obvious. A 4kHz transition band is more or less what you need to render it inaudible. Trouble is: 20kHz+4kHz44.1kHz/2... Actually most filters do have a 4.1kHz transition band on account of cost saving (look up halfband filter). What this means is that most converters do not satisfy the Nyquist criterium. This is not very audible, but still the world would have been a different place had we standardized on 48kHz with a non-halfband filter with a 4kHz transition band. The whole Hirez thing would have gone nowhere. g. Exactly. Count on it that most lay people think that sampling means that you can't know the moment something happens (e.g. zero crossings) with better precision that one sampling period. That's obvious bollocks. It is precisely the LPF's task to insure that such information is coded with essentially infinite precision (same limit as an ordinary noise limited low-pass filtered channel). There is no deficiency in the ability of digital audio to encode timing. The only resolution that high sampling rates add is the ability to distinguish two closely spaced events (as in, one sampling period apart). But that argument is better carried through in the frequency domain. I think that for your own sanity, whenever people are debating what is essentially a specialised subject using vague terminology, you should simply say to each his own and wander off. People who debate sampling theory are not that much different from those who debate evolution theory. It too is a remarkably precise and powerful theory which is only being debated by lay people because they have an emotional stake in its consequences. Regarding NOS: such converters have a frequency response of sin(pi*f/fs)/(pi*f/fs). This causes its characteristic sound. A friend of mine who is a mastering engineer once came raving about some box by Altmann. So I told him to upsample his audio 2x, then mix it with itself shifted 1 sample, take it back down 2x and listen what it does on a real DAC. The result was as predicted. This signal through his normal DAC sounded exactly like the original signal through the Altmann. Theory wins, again. Regarding apodizing: I saw Peter's presentation of that. He does with plastic slides stuff that I've yet to see a powerpoint rodeo do. Essentially he takes two premises from the opinion circuit without passing judgment but merely looks where they lead, to wit: what if the transition band determines audibility and what if pre-ringing is audible, and inband phase shift is audible too. Based on these two he then designs filters that are flat in magnitude and linear in phase up to 20kHz and then roll off gently to hit zero at fs/2. Now, if you look at it closely this means that his design method as applied to a 44.1kHz sampling rate will yield an ordinary sharp, linear-phase filter. You need a high sampling rate for apodizing filters to make sense. At 96kHz the filter starts rolling off gently towards cut-off at 48kHz. At that point the question becomes: OK so how does this compare with a sharp filter cutting off at 40kHz? Ri-ight. So after finding it hard to obtain solid double-blind data for 20kHz band-limited audio we're now about to embark on a quest for the ideal filter at 40kHz. You can imagine why it's not catching on. -- TheOctavist VortexboxSBT(stock)Forssell MDAC-2Klein and Hummell 0300D Sota Sapphire/Lyra KleosBespoke Valve Phono StageMastersound Due VentiLink Audio K100 TheOctavist's Profile: http://forums.slimdevices.com/member.php?userid=52700 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
adamdea;689865 Wrote: Hi TR, did you get any further reply from your pals? My it has gone quiet all of a sudden on this forum. Not yet..but I will soon! if not, ill phone em. :) btw, Adam, if you have any specific in depth questions...let me know, ill send em up the chain...and for that matter, the legendary engineer Tony Faulkner helps me a lot too, so if you have any recording engineering questions... -- TheOctavist VortexboxSBT(stock(TT failed dbt)Forssell MDAC-2Klein and Hummell 0300D Sota Sapphire/Lyra KleosBespoke Valve Phono StageMastersound Due VentiLink Audio K100 TheOctavist's Profile: http://forums.slimdevices.com/member.php?userid=52700 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
my old ears stop at about 12-13kHz -- finnbrodersen Some version of SBServer running on a HP EX490 home server SBReceiver -- NAD C162+C272 -- DALI IKON 6 (let's call it MidFi) finnbrodersen's Profile: http://forums.slimdevices.com/member.php?userid=17360 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
TheOctavist;689177 Wrote: ive asked all my elite audio friends, Adam. more to follow. Hi TR, did you get any further reply from your pals? My it has gone quiet all of a sudden on this forum. -- adamdea adamdea's Profile: http://forums.slimdevices.com/member.php?userid=37603 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
So here's a question somewhat related My DAC has multiple filter settings, I'm interested in why they chose any 2 parituclar filter combination to apply for low and high res. More specifically the last 2 settings: Setting 5, Minimum Phase Apodizing used for low res, anything above 24/48 uses Linear Phase Apodizing. Or it could be toggled to do the exact opposite with setting 4. http://www.stevehoffman.tv/forums/archive/index.php/t-239298.html http://hifiduino.blogspot.com/2009/05/wm8741-digital-filters.html -- Jeff Flowerday Jeff Flowerday's Profile: http://forums.slimdevices.com/member.php?userid=15883 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
We had this in another thread already. At Steve Hoffmans forums you can read a lot fuzzy statements, so don´t give that to much weight. The other thread shows exctly the misleading pics i mentioned before. Make these pics spectral and you´ll see all this post and pre stuff happens well above 20kHz if done correctly. Even the aliasing back can be above 20kHz, no problem. No one can really hear if the noise above 20Khz is music or aliasiad garbage. You may try to create a file with no content below 20kHz and abx it, good luck!! :) Also these apodizing and minimum or intermediate phase as far as i tested them clearly alter frequencies below 20kHz and may be audible just because of that. You won´t see that on that funny impulse pic. Also imagine the studio engineer already did the downsampling with some minimun filter and now you apply one again? In theory you must fiddle with a setting for every single recording. One other thing is that if all the junk above 20kHz changes the way your audio equipment sounds it is time to wonder. -- Wombat Transporter (modded) - RG142 - Avantgarde Acoustic based 500VA monoblocks - Sommer SPK240 - self-made speakers Wombat's Profile: http://forums.slimdevices.com/member.php?userid=4113 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Wombat;689287 Wrote: I am no pro but recording, editing, applying effects of cause should be done at the highest rate it is comfortable to work with. Why not if the power is simply there with todays hardware. I did read about several plugins for VST hosts that indeed work at higher sampling and bitrate internaly. For the final distribution to us listeners i still think anything higher as 16/44.1 will hardly give us any benefit. Of cause when this last step is done correctly. That was my piont, it has merits to produce and record in hirez, however the delivery format to consumer is another question . In every tread we discuss this recording producing and playback is mixed up, they deserve separat treatment . I do believe in 24/96 or 24/48 for another reason , eq and processing does not stop in the recording studio anymore , I have at least 6 digital xover pionts DRC Eq and spatial processing, digital volume controll going on in my home theater . To Meridians credit it can be said that this seems to work very well with any source material, the benefit may be more theoretical and possibly measurable , but audiability may be another question. -- Mnyb Main hifi: Touch + CIA PS +MeridianG68J MeridianHD621 MeridianG98DH 2 x MeridianDSP5200 MeridianDSP5200HC 2 xMeridianDSP3100 +Rel Stadium 3 sub. Bedroom/Office: Boom Kitchen: Touch + powered Fostex PM0.4 Misc use: Radio (with battery) iPad 64gB wifi +3g with iPengHD SqueezePad (in storage SB3, reciever ,controller ) Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
TheOctavist;689177 Wrote: ive asked all my elite audio friends, Adam. more to follow. Fantastic TR I think there are 2 related issues -whether 44.1 has any advantages for playback - whether there are advantages in any particular type of filter for reconstruction downsampling or bandlimiting (assuming we already have a standard linear phase half band filter) -- adamdea adamdea's Profile: http://forums.slimdevices.com/member.php?userid=37603 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Mnyb;689195 Wrote: Are we mixing two things in this tread recording and playback ? Are they not all kinds of very good reasons to record at higher rates 24/96 produce the thing and then properly normalise downsample and dither and have a well produced 16/44.1 CD . And this sound just fine , it is very likely that most of us would fail to abx this. Is this not in fact the typical mo of modern recording ? ( with the destructive loudness war phase removed ) Dow sampling well done modern hirez production is one thing to abx . ( not one off hdcraps 45y old analog rock classics I bet here 14bits are ok ). I can donate some itrax tunes ( aix ) for the purpose or a chesky . But recording all tracks at 16/44.1 and then produce the whole shebang at this rate ? And do the same process at higher rate in parallell ? This would be interesting to abx. The pro's that are in this tread, are there any ADC's you would consider transparent especially one that also can do 16/44.1 as oposed to the modern 24/48-192k setting and have 1 of them ? Wombat or phil may be able to find studio time ? Afaik your studio software would remeber what you did when producing so repeating these steps would be feasible. What would a modern DAW do whith 16/44.1 original data would it upsample and turn it to 32 bit floating piont data so that all plugins eq and stuff would work transparently ? Can this be defeated ? Anyone any good at singing or playing ? I am no pro but recording, editing, applying effects of cause should be done at the highest rate it is comfortable to work with. Why not if the power is simply there with todays hardware. I did read about several plugins for VST hosts that indeed work at higher sampling and bitrate internaly. For the final distribution to us listeners i still think anything higher as 16/44.1 will hardly give us any benefit. Of cause when this last step is done correctly. -- Wombat Transporter (modded) - RG142 - Avantgarde Acoustic based 500VA monoblocks - Sommer SPK240 - self-made speakers Wombat's Profile: http://forums.slimdevices.com/member.php?userid=4113 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Archimago;689023 Wrote: Hi all, It's one of those questions I don't recall much discussion about. It comes about because of music like Kent Poon's Audiophile Jazz Prologue III (where the hi-res material looks like upsampled 44/48! yet he claims it was natively recorded at hi-res but presumably a filter added in postprocessing). If I'm recording some audio in PCM that contains no frequency 20kHz, is there any benefit to recording this at 88kHz or more? That is, does sampling theory suggest that the improved temporal resolution will add anything once the signal is reconstructed in the DAC? I've always assumed that the improved temporal resolution should give us better transient response (ie. the slam of the kick drum might just arrive slightly quicker and more precisely, whether the ear/brain detects it is another matter). I'm thinking it might not be so obvious once we go through the science of it all... Regards, Arch Shannon/Nyquist theory is by clear... To perfectlyreconstruct a signal of Frequency F you need a sampling frequency of 2F. The are of course some subtle provisos to this theory. however there is definitely no improved temporal resolution to be had - that is an audio myth, just like the classically misleading (indeed poisonous) staircase diagram that implies a need for lots more samples/bits... Coz you know 16/24 @ 44.1 just ain't enough to capture the subtleties... :-- The real question is is 20khz enough? I reckon that for 99.999% of people who even care about this question, 15khz is plenty! :-) -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal... Touch(wired/W7)+Teddy Pardo PSU - Audiolense 3.3/2.0+INGUZ DRC - MF M1 DAC - Linn 5103 - full Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Pekin Tuner, Townsend Supertweeters,VdH Toslink,Kimber 8TC Speaker Chord Signature Plus Interconnect cables Stax4070+SRM7/II phones Kitchen Boom, Outdoors: SB Radio, Harmony One remote for everything. Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Phil Leigh;689054 Wrote: ... The real question is is 20khz enough? I reckon that for 99.999% of people who even care about this question, 15khz is plenty! :-) Do we still need supertweeters then? :-) -- vett93 Main system: Source: Transporter, modded by ModWright: http://www.modwright.com/modifications/transporter-truth-mods.php Preamp: Dude from Tube Research Labs: http://www.tuberesearchlabs.com/products/dude.html Amp: NP100 Platinum from AltaVista Audio: http://www.altavistaaudio.com/np100.html Speakers: Alto Utopia Be from Focal-JMLab: http://www.focal.com/en/home-audio-loudspeakers/hifi-speakers/floorstanding-speakers/alto-utopia-be.php vett93's Profile: http://forums.slimdevices.com/member.php?userid=13301 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Like Phil already pointed out there is lots of misinformation around especialy by some audio hardware sellers that argue with impressive pics. Impulses in lowres suddenly look ugly and look slow what in reality simply is the visualisation of a lowpass, nothing to wurry about. When lame mp3 developement was in earlier state we once tested where to set a lowpass and even the for sure way above average, younger (golden) ears were not able to spot lowpassing in music at 18.5khz while they could easily hear a 20kHz sinuid. -- Wombat Transporter (modded) - RG142 - Avantgarde Acoustic based 500VA monoblocks - Sommer SPK240 - self-made speakers Wombat's Profile: http://forums.slimdevices.com/member.php?userid=4113 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
vett93;689065 Wrote: Do we still need supertweeters then? :-) Depends where they crossover :-) -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal... Touch(wired/W7)+Teddy Pardo PSU - Audiolense 3.3/2.0+INGUZ DRC - MF M1 DAC - Linn 5103 - full Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Pekin Tuner, Townsend Supertweeters,VdH Toslink,Kimber 8TC Speaker Chord Signature Plus Interconnect cables Stax4070+SRM7/II phones Kitchen Boom, Outdoors: SB Radio, Harmony One remote for everything. Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Some interesting read about the temporal masking and its need or not for higher sampling rate. http://www.hydrogenaudio.org/forums/index.php?showtopic=73598hl=impulsest=0 You really have to read thru completely and try to understand as much as possible. Me don´t but find it interesting nonetheless :) -- Wombat Transporter (modded) - RG142 - Avantgarde Acoustic based 500VA monoblocks - Sommer SPK240 - self-made speakers Wombat's Profile: http://forums.slimdevices.com/member.php?userid=4113 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
You can of-course get rid of ADC artifacts lets say a not so god filter implementation by recording in higher FS . But down-sampling it to 44.1 should be transparent ? The example is a bit theoretical ? normally a lot off post-processing is used so working on 24/96 or 32-64 bit float in the software can't hurt. But I agree on the general principle (I could not do otherwise ,mr nyqvist stands) What about the bith dept ? 24 bit is a healthy marginal , was not some older CD's more like 13bit and no dithering at all ? yuk. -- Mnyb Main hifi: Touch + CIA PS +MeridianG68J MeridianHD621 MeridianG98DH 2 x MeridianDSP5200 MeridianDSP5200HC 2 xMeridianDSP3100 +Rel Stadium 3 sub. Bedroom/Office: Boom Kitchen: Touch + powered Fostex PM0.4 Misc use: Radio (with battery) iPad 64gB wifi +3g with iPengHD SqueezePad (in storage SB3, reciever ,controller ) Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
This is a very good question. Hopefully Teddy Ray may be able to help out with his very high powered friends. I have been trying really hard to grasp the temporal resolution issue and have found it really difficult. It seems to have been kicked off in audiophile circles by the NOS dac bollocks and (separately and indirectly) by an article by Craven for AES about the desirability of apodising/ minimum phase filters [not quite the same thing I know]. These filters are somewhat in vogue although neither weiss nor briscasti seem to use them. Annoyingly I think that this is an incredibly difficult area and the basic digital electronics text books i have read have very little on it. Just to get things started here are a couple of thoughts [APOLOGIES I NOW REALISE I HAVE GONE OFF ON A BIT OF A RAMBLE BUT HERE GOES ANYWAY}- a. AFAIK there really isn't any evidence that we can hear above 20Khz (make that 15 for most of us) b. in order to be nyquist compliant before sampling at 44.1kHz (or downsampling to 44.1), the signal has to be band limited to 22.05kHz or lower. c. there is an issue about whether the effect of this band limitation could be audible. d. we were talking here about the band limation prior to the ADC (or resampling) NOT in your DAC. e. but wait! the band limitation at the ADC has been created by a number of processes starting with the mic and then (maybe the mixer etc and the tape if its an old analog recording. So in order to analyse out the effect of band limitation you have to look at this chain as a whole f. time domain and frequency domain analysis are basically two sides of the same coin -if you limit the max frequency you must have an impact in the time domain. g. but this expression temporal resolution is a real bugger. AFAIK it has no fixed meaning. It is bandied around by certain audiophiles as a possible peg o which to hang their belief that digital especially properly filtered digital doesn't sound good. h if you don't believe me check out the kunchur/ JJ debate in which Kunchur made an utter arse of himself, despite being a genuine physicist, when he suggested that temporal resolution was limited to the inter sample period. i strictly speaking looking at the OP it seems to me that the answer is that if there is no information in the original signal about 20Khz there cannot be any time resolution issue with 20kHz band limitation. This is because a proper filter should have no impact below the stop band. It is therefore trivial that there could not be any information loss. j. that answer might be a bit to smart arse though- the real question is whether, assuming there was information above 20KhZ in the original signal, the band limitation prior to sampling might still have some detectable effect on the signal. k Any band limitation must affect the signal in the time domain. In particular the maximum frequency determines the maximum steepness of the slope in the time domain. So the band limited signal has to be spread out in the time domain if higher frequencies are filtered out. BUT CAN ANYONE ACTUALLY HEAR THIS? IF THEY CAN HEAR THE DIFFERENCE BETWEEN FIKLTERED AND UNFILTERED, the IS ONE Sensible) FILTER BETTER THAN ANOTHER l. this is where we get into pre ringng an post ringing. IN order to make a filter which perfectly complies with nyquist it should in principle be a linear phase filter. This will spread out the signal equally in both directions (earlier and later) . But according to auipophile magazines this apparently means pre ringing and this is apparently bad. m I would love to see 1) a demonstration of how a real world signal is affected by a linear phase filter with a passband up to 20hZ or so and proper attenuation at nyquist. Weirdly I have not actually seen one 2) some evidence that people can hear the difference between the unfiltered and filtered signal and the difference between MP and LP filters.. -- adamdea adamdea's Profile: http://forums.slimdevices.com/member.php?userid=37603 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Just create yourself such an impulse and apply a lowpass or resample it. The post and preringing only happens around fs/2 so above 20kHz. I did some and with a gentle filter kicking in around 20khz there is virtualy no ringing left. Of cause the picture of simply the impulse, not its spectrum is welcome for marketing :) -- Wombat Transporter (modded) - RG142 - Avantgarde Acoustic based 500VA monoblocks - Sommer SPK240 - self-made speakers Wombat's Profile: http://forums.slimdevices.com/member.php?userid=4113 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
You also need to consider the sampling rate of the human ear and the inter-sample interpolation (and all of the other heavyweight processing) in the brain... -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal... Touch(wired/W7)+Teddy Pardo PSU - Audiolense 3.3/2.0+INGUZ DRC - MF M1 DAC - Linn 5103 - full Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Pekin Tuner, Townsend Supertweeters,VdH Toslink,Kimber 8TC Speaker Chord Signature Plus Interconnect cables Stax4070+SRM7/II phones Kitchen Boom, Outdoors: SB Radio, Harmony One remote for everything. Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Wombat;689087 Wrote: Just create yourself such an impulse and apply a lowpass or resample it. The post and preringing only happens around fs/2 so above 20kHz. I did some and with a gentle filter kicking in around 20khz there is virtualy no ringing left. Of cause the picture of simply the impulse, not its spectrum is welcome for marketing :) I agree that the impulse response is very misleading since it represents the response of the filter to an impossible input. BUt still the effect of pre-ringing is confusing. Although it represents to effect of the filter cutting off frequencies above the stop band AFAIK it supposedly spreads out energy throughout the passband. This is where i get confused because it supposedly does so even though the filter has a flat response in the passband- how can it do that (PAGING TEDDY RAY) -- adamdea adamdea's Profile: http://forums.slimdevices.com/member.php?userid=37603 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Phil Leigh;689088 Wrote: You also need to consider the sampling rate of the human ear and the inter-sample interpolation (and all of the other heavyweight processing) in the brain... Absolutely, and i think that saying you can detect the time domain effects is just sneaking through the back door the argument that you can hear over 20KhZ -- adamdea adamdea's Profile: http://forums.slimdevices.com/member.php?userid=37603 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
adamdea;689091 Wrote: Absolutely, and i think that saying you can detect the time domain effects is just sneaking through the back door the argument that you can hear over 20KhZ Agreed. Most of this is hogwash dreamt up by people who heard early digital and felt it was bad (which it mostly was)... And then invented a whole fake mythology about why it was bad and why it would never be good. Fools. -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal... Touch(wired/W7)+Teddy Pardo PSU - Audiolense 3.3/2.0+INGUZ DRC - MF M1 DAC - Linn 5103 - full Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Pekin Tuner, Townsend Supertweeters,VdH Toslink,Kimber 8TC Speaker Chord Signature Plus Interconnect cables Stax4070+SRM7/II phones Kitchen Boom, Outdoors: SB Radio, Harmony One remote for everything. Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
adamdea;689090 Wrote: I agree that the impulse response is very misleading since it represents the response of the filter to an impossible input. BUt still the effect of pre-ringing is confusing. Although it represents to effect of the filter cutting off frequencies above the stop band AFAIK it supposedly spreads out energy throughout the passband. This is where i get confused because it supposedly does so even though the filter has a flat response in the passband- how can it do that (PAGING TEDDY RAY) I lately did some in a different forum, first some kind of Apodizing against steep linear. http://imageshack.us/photo/my-images/718/impulsapo.png/ Second is a gentle linear: http://imageshack.us/photo/my-images/12/sox90a.png/ You see it shouldn´t touch the audible band at all. -- Wombat Transporter (modded) - RG142 - Avantgarde Acoustic based 500VA monoblocks - Sommer SPK240 - self-made speakers Wombat's Profile: http://forums.slimdevices.com/member.php?userid=4113 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
This is very intersting- what does the unfiltered signal look like? -- adamdea adamdea's Profile: http://forums.slimdevices.com/member.php?userid=37603 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Original is 24/96 full scale impulse that looks exactly like the signal below 20khz on these linears up to 48kHz. -- Wombat Transporter (modded) - RG142 - Avantgarde Acoustic based 500VA monoblocks - Sommer SPK240 - self-made speakers Wombat's Profile: http://forums.slimdevices.com/member.php?userid=4113 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Nyquist theorema tells there is no benefits but is based on the following assumptions: 1) sampled signal is made of perfect dirac pulses... practically they will look like square pulses resulting in a quite bad low pass sin x/x filtering that zeroes at 1/T where T is the width of the pulse (staircase sampled signal being the worst with 1/T equals to sample freq) 2) sampled pulse has a constant time period... but in reality time period is varying due to jitter 3) signal reconstruction is using perfect brickwall filters... but in practice it is very difficult to have steep filter slope without artifacts In conclusion, there might be a (big?) gap between theory and practice. According to the 3 assumptions above, here are the (audible?) benefits of 96khz: 1) higher sample freq is reducing the low pass effect of square pulses, rejecting the resulting zeroes to higher freq 2) doubling the number of pulses adds redundancy to the signal that increases immunity to jitter 3) less steep brickwall filters are needed for signal reconstruction, reducing artifacts and improving linearity So hi res might technically improve the accuracy of reconstructed signal even if baseband signal does not contain any freq above 20 khz. The question remains however: are those benefits audible or not? I'd say it makes it at least more robust against less than optimal receiver implementation. -- evdplancke evdplancke's Profile: http://forums.slimdevices.com/member.php?userid=43147 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
evdplancke;689106 Wrote: Nyquist theorema tells there is no benefits but is based on the following assumptions: 1) sampled signal is made of perfect dirac pulses... practically they will look like square pulses resulting in a quite bad low pass sin x/x filtering that zeroes at 1/T where T is the width of the pulse (staircase sampled signal being the worst with 1/T equals to sample freq) 2) sampled pulse has a constant time period... but in reality time period is varying due to jitter 3) signal reconstruction is using perfect brickwall filters... but in practice it is very difficult to have steep filter slope without artifacts In conclusion, there might be a (big?) gap between theory and practice. According to the 3 assumptions above, here are the (audible?) benefits of 96khz: 1) higher sample freq is reducing the low pass effect of square pulses, rejecting the resulting zeroes to higher freq 2) doubling the number of pulses adds redundancy to the signal that increases immunity to jitter 3) less steep brickwall filters are needed for signal reconstruction, reducing artifacts and improving linearity So hi res might technically improve the accuracy of reconstructed signal even if baseband signal does not contain any freq above 20 khz. The question remains however: are those benefits audible or not? I'd say it makes it at least more robust against less than optimal receiver implementation. There's still no irrefutable evidence that anyone can hear the difference - you'd think by now the Net would have at least a few conclusive studies? -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal... Touch(wired/W7)+Teddy Pardo PSU - Audiolense 3.3/2.0+INGUZ DRC - MF M1 DAC - Linn 5103 - full Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Pekin Tuner, Townsend Supertweeters,VdH Toslink,Kimber 8TC Speaker Chord Signature Plus Interconnect cables Stax4070+SRM7/II phones Kitchen Boom, Outdoors: SB Radio, Harmony One remote for everything. Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
evdplancke;689106 Wrote: Nyquist theorema tells there is no benefits but is based on the following assumptions: 1) sampled signal is made of perfect dirac pulses... practically they will look like square pulses resulting in a quite bad low pass sin x/x filtering that zeroes at 1/T where T is the width of the pulse (staircase sampled signal being the worst with 1/T equals to sample freq) 2) sampled pulse has a constant time period... but in reality time period is varying due to jitter 3) signal reconstruction is using perfect brickwall filters... but in practice it is very difficult to have steep filter slope without artifacts In conclusion, there might be a (big?) gap between theory and practice. According to the 3 assumptions above, here are the (audible?) benefits of 96khz: 1) higher sample freq is reducing the low pass effect of square pulses, rejecting the resulting zeroes to higher freq 2) doubling the number of pulses adds redundancy to the signal that increases immunity to jitter 3) less steep brickwall filters are needed for signal reconstruction, reducing artifacts and improving linearity So hi res might technically improve the accuracy of reconstructed signal even if baseband signal does not contain any freq above 20 khz. The question remains however: are those benefits audible or not? I'd say it makes it at least more robust against less than optimal receiver implementation. I am not really sure what you mean by 1)except as a corollary of 3). and I'm not sure about 2) either -surely a higher sampling rate would require more accurate timing in the ADC? not that I think this is an issue. The real point is that doubling fs halves the quantisation noise in the audible spectrum.This the equivalent of adding 1 bit albeit very inefficiently since you have doubled the data rate whilst increasing the amount of information by the same amount you could have achieved by adding one bit which would have increased the data rate by 1/16.It does give you some room to play with for noise shaping though. I think 3) is the real time domain issue. But it's worth pointing out that the fundamental issue is that increasing fs enables you to have less steep filter in the anti alias stage of ADC. But it all begs the question - given the ability to create very steep digital filters with negligible passband ripple or phase issues, what are the artefacts? I note however that daniel weiss indicated in an interview that he thought 16/88 would be more beneficial as a consumer format than 24/48. I don't think he spelt this out but I assume it was because he thought there was chance that there was something in the time domain issues. Even then though it's worth stressing that there should not be any time domain issue if the pre-filtering pre ADC signal has no energy above 20kHz - there will not be any time smear then![I Hold my breath and wait to be shown up as an idiot] Equally If there is no signal above 20KHz in the 24/96 file then either there was none in the pre recording sound [no time smear with sensible filtering] or there was but it has been filtered out anyway ie the time smear will have occured. . IN that case I can't see how there could be any worthwhile improvement in a 96kHz file over a 44.1 kHz. -- adamdea adamdea's Profile: http://forums.slimdevices.com/member.php?userid=37603 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
adamdea;689124 Wrote: I am not really sure what you mean by 1)except as a corollary of 3). 1) is different from 3) because the low pass effect will affect the baseband signal: a convolution of a square pulse with perfect dirac pulse train in the time domain corresponds to multiplying the signal in the frequency domain by a very poor sinx/x lowpass filter. This has nothing to do with the reconstruction filter used for 3): this is a lowpass distortion BEFORE reconstruction, that is definitely altering the baseband signal in an extent inversely proportional to the square pulse width. -- evdplancke evdplancke's Profile: http://forums.slimdevices.com/member.php?userid=43147 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
There are a number of rules in the audio world that haven't held up. For long time it was considered that we could only hear differences of at least 1 dB. That has been demonstrated to not be correct. I remember reading about a double blind test in Stereo Review that went bad because there was a .1 dB diffenence in levels. The listeners could pick it up. Bell Labs was able to show that filtering out everything above 30 KHz was detectable by a person who was tone deaf above 10 KHz. Jim Smith in his book Get Better Sound has a great story about discovering that he could pick out sounds that were below the noise floor in analog recordings but not in a digital recording of the same. The human ear is pretty amazing. The naysayers about cables always claim that only resistance and reactance count. We in the wireless industry are being increasingly plagued by a distortion called PIM, which occurs in cables and connectors. It is every bit as possible in the audio range as the microwave. And no one except maybe a specially built research lab can measure PIM in the audio frequency range. We only recently have developed the ability to measure it easily in the microwave range, which is orders of magnitude easier. If people are consistently hearing differences even though the theory or instruments say they shouldn't we should assume it is always a case of self delusion. We knowledge is dwarfed by our ignorance. -- regalma1 regalma1's Profile: http://forums.slimdevices.com/member.php?userid=6658 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
regalma1;689163 Wrote: There are a number of rules in the audio world that haven't held up. For long time it was considered that we could only hear differences of at least 1 dB. That has been demonstrated to not be correct. I remember reading about a double blind test in Stereo Review that went bad because there was a .1 dB diffenence in levels. The listeners could pick it up. Bell Labs was able to show that filtering out everything above 30 KHz was detectable by a person who was tone deaf above 10 KHz. Jim Smith in his book Get Better Sound has a great story about discovering that he could pick out sounds that were below the noise floor in analog recordings but not in a digital recording of the same. Please link to some serious study that claims only steps of 1db are audible. Of cause it is much smaller steps and when you are at it the study that shows 0.1dB. Same goes for the signal filtered at 30Khz. -- Wombat Transporter (modded) - RG142 - Avantgarde Acoustic based 500VA monoblocks - Sommer SPK240 - self-made speakers Wombat's Profile: http://forums.slimdevices.com/member.php?userid=4113 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
regalma1;689163 Wrote: There are a number of rules in the audio world that haven't held up. For long time it was considered that we could only hear differences of at least 1 dB. That has been demonstrated to not be correct. I remember reading about a double blind test in Stereo Review that went bad because there was a .1 dB diffenence in levels. The listeners could pick it up. Bell Labs was able to show that filtering out everything above 30 KHz was detectable by a person who was tone deaf above 10 KHz. Jim Smith in his book Get Better Sound has a great story about discovering that he could pick out sounds that were below the noise floor in analog recordings but not in a digital recording of the same. The human ear is pretty amazing. The naysayers about cables always claim that only resistance and reactance count. We in the wireless industry are being increasingly plagued by a distortion called PIM, which occurs in cables and connectors. It is every bit as possible in the audio range as the microwave. And no one except maybe a specially built research lab can measure PIM in the audio frequency range. We only recently have developed the ability to measure it easily in the microwave range, which is orders of magnitude easier. If people are consistently hearing differences even though the theory or instruments say they shouldn't we should assume it is always a case of self delusion. We knowledge is dwarfed by our ignorance. There is an easy answer to all this: a statistically significant double blind test. If such a test proves to an acceptable degree of certainty *that* a difference exists, then we can move on to investigating *why* it exists. But not until then, because there are an infinite number of things we could assume, and we don't have the time to investigate then all. -- darrell darrell's Profile: http://forums.slimdevices.com/member.php?userid=13460 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
evdplancke;689154 Wrote: 1) is different from 3) because the low pass effect will affect the baseband signal: a convolution of a square pulse with perfect dirac pulse train in the time domain corresponds to multiplying the signal in the frequency domain by a very poor sinx/x lowpass filter. This has nothing to do with the reconstruction filter used for 3): this is a lowpass distortion BEFORE reconstruction, that is definitely altering the baseband signal in an extent inversely proportional to the square pulse width. Are you referring here to aperture effect? I understand that this can be a problem, but can be compensated by equalisation or resampling to reduce the aperture ratio. But this is not resampling in the sense of increasing the sample rate. Wouldn't having a higher sample rates mean that your pulse train would need to be more perfect - a given pulse duration would now represent a higher proportion of the sample period surely(?) and would therefore reach zero order hold for a shorter pulse width . -- adamdea adamdea's Profile: http://forums.slimdevices.com/member.php?userid=37603 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Theoretical is If you say you hear this: NUTS ! -- pski real stereo doesn't just wake the neighbors, it -enrages- them.. It is truly the Golden Age of Wireless pski's Profile: http://forums.slimdevices.com/member.php?userid=15574 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Since here are so many members around that really believe they are above golden eared there is one big chance: I´d like the people from here bringing samples and honest testing showing to us all what the higher bandwith brings. Try to resample a version of your beloved showcase and offer your findings here. Do some foobar abx with a headset if you like at home and post the logs with all honesty here. Please no liquid soundstage bullshit, just plain abx. It is simple. Afterwards we can collect the positive results and dig deeper why you were positive. We can help each other with preparing the files. If all goes positive we may ask on hydrogenaudio for further backup. I think this can be some fun. I did a kind of this lately :) -- Wombat Transporter (modded) - RG142 - Avantgarde Acoustic based 500VA monoblocks - Sommer SPK240 - self-made speakers Wombat's Profile: http://forums.slimdevices.com/member.php?userid=4113 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
darrell;689167 Wrote: There is an easy answer to all this: a statistically significant double blind test. If such a test proves to an acceptable degree of certainty *that* a difference exists, then we can move on to investigating *why* it exists. But not until then, because there are an infinite number of things we could assume, and we don't have the time to investigate then all. AFAIK contrary to what regalma1 says there have been studies which have shown that people can tell properly low pass filtered material from the original with 40 kHz or whatever bandwidth. Plus we have to wonder why adults are not bothered by anti teenager mosquito devices, ultrasonic machinery or indeed noise shaping, -- adamdea adamdea's Profile: http://forums.slimdevices.com/member.php?userid=37603 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
ive asked all my elite audio friends, Adam. more to follow. -- TheOctavist VortexboxSBT(stock(TT failed dbt)Forssell MDAC-2Klein and Hummell 0300D Sota Sapphire/Lyra KleosBespoke Valve Phono StageMastersound Due VentiLink Audio K100 TheOctavist's Profile: http://forums.slimdevices.com/member.php?userid=52700 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
adamdea;689174 Wrote: Plus we have to wonder why adults are not bothered by anti teenager mosquito devices, ultrasonic machinery or indeed noise shaping, I have to disagree with at least the first part of this statement. About 4 years ago, I was curious about this mosquito device (in my mid-50's, then)---had just read something about itand found a number of audio clips of them on websites. So, I played a few and it bothered me plenty (and I took a blind test with my teenaged daughters administering it and passed with 100% accuracy)! Don't know whether or not I could hear it now, but I suspect I'm not the only adult that could hear it. My wife could not, though, and was absolutely convinced---much to our great hilarity---that we were playing mean tricks on her. -- rgro Rg System information Main: PS Audio Quintet Vortexbox Teddy Pardo PS, Touch (wired) Toslink Rega DAC LFD LE IV Signature amp VA Mozart Grands REL Acoustics R305. Home Theatre: Duet/SBR (Wired) Pioneer VSX 919 Energy Take 5 Classic 5.1. SBS 7.7.1 r33751 on a Vortexbox Appliance, V 2.0, Touch: FW 7.7.1 r9558. Duet: FW 7.7.1 r9557. rgro's Profile: http://forums.slimdevices.com/member.php?userid=34348 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
AFAIK the mentioned mosquito handy tone is at around 17kHz. Some years ago when it was trendy i tried these tones and heard them clearly. -- Wombat Transporter (modded) - RG142 - Avantgarde Acoustic based 500VA monoblocks - Sommer SPK240 - self-made speakers Wombat's Profile: http://forums.slimdevices.com/member.php?userid=4113 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Wombat;689180 Wrote: AFAIK the mentioned mosquito handy tone is at around 17kHz. Some years ago when it was trendy i tried these tones and heard them clearly. According to Wikipedia it's 17.4kHz. Glad to know there's more than one old fart whose ears still work o.k.! -- rgro Rg System information Main: PS Audio Quintet Vortexbox Teddy Pardo PS, Touch (wired) Toslink Rega DAC LFD LE IV Signature amp VA Mozart Grands REL Acoustics R305. Home Theatre: Duet/SBR (Wired) Pioneer VSX 919 Energy Take 5 Classic 5.1. SBS 7.7.1 r33751 on a Vortexbox Appliance, V 2.0, Touch: FW 7.7.1 r9558. Duet: FW 7.7.1 r9557. rgro's Profile: http://forums.slimdevices.com/member.php?userid=34348 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
rgro;689183 Wrote: According to Wikipedia it's 17.4kHz. Glad to know there's more than one old fart whose ears still work o.k.! Heh! I bet many still can hear this. Nonetheless i have to admit the hearing slowly degrades no matter how much i try to guard my ears. Some things simply don´t jump on me soundwise like before. I was used to hear several hard to hear glitches in mp3 encoding with ease. The same kind of glitches become harder for me. Still i can hear up to ~18kHz with my early 40s. I sometimes wonder how some of the reviewers that often must be in the 60s claim all kinds of things they still hear. -- Wombat Transporter (modded) - RG142 - Avantgarde Acoustic based 500VA monoblocks - Sommer SPK240 - self-made speakers Wombat's Profile: http://forums.slimdevices.com/member.php?userid=4113 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
The temporal resolution of 44.1 kHz audio is about 1/(44100*65536*2*pi) seconds, which is so far below any detectable difference that I can not possibly imagine an ydifference. I would love to stomp out this time resolution crap that we see all the time in the high end, it's due to some people who don't understand the concepts around sampling, how filtering works, etc -- TheOctavist VortexboxSBT(stock(TT failed dbt)Forssell MDAC-2Klein and Hummell 0300D Sota Sapphire/Lyra KleosBespoke Valve Phono StageMastersound Due VentiLink Audio K100 TheOctavist's Profile: http://forums.slimdevices.com/member.php?userid=52700 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Are we mixing two things in this tread recording and playback ? Are they not all kinds of very good reasons to record at higher rates 24/96 produce the thing and then properly normalise downsample and dither and have a well produced 16/44.1 CD . And this sound just fine , it is very likely that most of us would fail to abx this. Is this not in fact the typical mo of modern recording ? ( with the destructive loudness war phase removed ) Dow sampling well done modern hirez production is one thing to abx . ( not one off hdcraps 45y old analog rock classics I bet here 14bits are ok ). I can donate some itrax tunes ( aix ) for the purpose or a chesky . But recording all tracks at 16/44.1 and then produce the whole shebang at this rate ? And do the same process at higher rate in parallell ? This would be interesting to abx. The pro's that are in this tread, are there any ADC's you would consider transparent especially one that also can do 16/44.1 as oposed to the modern 24/48-192k setting and have 1 of them ? Wombat or phil may be able to find studio time ? Afaik your studio software would remeber what you did when producing so repeating these steps would be feasible. What would a modern DAW do whith 16/44.1 original data would it upsample and turn it to 32 bit floating piont data so that all plugins eq and stuff would work transparently ? Can this be defeated ? Anyone any good at singing or playing ? -- Mnyb Main hifi: Touch + CIA PS +MeridianG68J MeridianHD621 MeridianG98DH 2 x MeridianDSP5200 MeridianDSP5200HC 2 xMeridianDSP3100 +Rel Stadium 3 sub. Bedroom/Office: Boom Kitchen: Touch + powered Fostex PM0.4 Misc use: Radio (with battery) iPad 64gB wifi +3g with iPengHD SqueezePad (in storage SB3, reciever ,controller ) Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Awesome discussion guys! I must admit a lot of the science is over my head but great to read so many knowledgeable posts; clearly discussion an order of magnitude beyond much of the bickering over the last couple weeks. At 40 years old now, my frequency threshold is around 17kHz. I've ABX'ed 24/96 songs downsampled to 16/44 through pretty reasonable hardware attached to my main computer (E-Mu0404USB -- Music Hall Ph25.2 headphone amp -- Sennheiser HD800) unsuccessfully. The more I test this out for myself, the less I'm tempted to buy any more 'hi-res' music. I really do hope the loudness war ends at some point to elevate the mastering job on more modern music as that is what seems to be the real 'quality limiting' piece these days. I suspect that much of the raving around hi-res music whether DVD-A or SACD has been the fact that they were often mastered at a higher level if the science is pretty clear that ears/brains are unlikely to experience an improvement just from the specs... -- Archimago Archimago's Profile: http://forums.slimdevices.com/member.php?userid=2207 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Mnyb;689195 Wrote: Anyone any good at singing or playing ? im an engineer, and have nice recording gear. I use MYTEK AD/DA transparent. superb. what do you need? -- TheOctavist VortexboxSBT(stock(TT failed dbt)Forssell MDAC-2Klein and Hummell 0300D Sota Sapphire/Lyra KleosBespoke Valve Phono StageMastersound Due VentiLink Audio K100 TheOctavist's Profile: http://forums.slimdevices.com/member.php?userid=52700 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
Mnyb;689195 Wrote: What would a modern DAW do whith 16/44.1 original data would it upsample and turn it to 32 bit floating piont data so that all plugins eq and stuff would work transparently ? Can this be defeated ? Anyone any good at singing or playing ? yes, most all use 32 bit FP, other than REAPER(which I think uses 64) it can be disabled on some, yes. like my sequoia workstation(which also allows me to hear the two rates simultaneously.. -- TheOctavist VortexboxSBT(stock(TT failed dbt)Forssell MDAC-2Klein and Hummell 0300D Sota Sapphire/Lyra KleosBespoke Valve Phono StageMastersound Due VentiLink Audio K100 TheOctavist's Profile: http://forums.slimdevices.com/member.php?userid=52700 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Theoretical benefits to hi-res if only max 20kHz signal?
If you try hf test tones at home make sure the DAC works properly . I tried with my m-audio computer speakers, but my old soundblaster souncards is not up to it or I have severe audio subsystem problems on the desktop or both. I get aliasing or similar artefacts you can definitely hear something when playing tones close to 20k :) I'll bet some of the cargo cult engineered nos dacs or similar also would fail in this respects so using properly designed equipment is paramount as usual. -- Mnyb Main hifi: Touch + CIA PS +MeridianG68J MeridianHD621 MeridianG98DH 2 x MeridianDSP5200 MeridianDSP5200HC 2 xMeridianDSP3100 +Rel Stadium 3 sub. Bedroom/Office: Boom Kitchen: Touch + powered Fostex PM0.4 Misc use: Radio (with battery) iPad 64gB wifi +3g with iPengHD SqueezePad (in storage SB3, reciever ,controller ) Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=93483 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
