[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
325xi Wrote: > I recall some recent thread discussing Altmann's devices and lack of any > meaningful technical information about them on his sites. I just can't > allow to myself to invest another $1K into some "back box" not analysed > and not discussed from technical perspective. I agree and thought long and hard about it too. In the end it came down to the fact that Altmann offers a FULL refund if not happy with the improvement - so I took a punt. I suspect that if you took these little boxes to pieces there'd just be a handful of CMOS logic chips in there - but frankly I don't care coz it seems to work to me... -- Phil Leigh Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Phil Leigh Wrote: > The Altmann boxes make a big difference for me - you should try them > (sb-JISCO-UPCI-Dac de Jour...) I recall some recent thread discussing Altmann's devices and lack of any meaningful technical information about them on his sites. I just can't allow to myself to invest another $1K into some "back box" not analysed and not discussed from technical perspective. -- 325xi 325xi's Profile: http://forums.slimdevices.com/member.php?userid=5661 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
325xi Wrote: > Altmann's boxes are said to do wonders to both sound and jitter :) , > although I have no idea how much hype in it... http://www.jitter.de/ The Altmann boxes make a big difference for me - you should try them (sb-JISCO-UPCI-Dac de Jour...) -- Phil Leigh Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Cool, thanks for the explination. Dan also mentioned that my DA10 has the RAM buffer as well... which I was unaware of. ;) -- philodox box clever, watch your system come together crazy weather at the end of my tether ::る:: heavily modded akg k340 < xlr out < lavry *black* da10 > headphone out > john grado hf-1 slim devices squeezebox /\ ultimate power cell 200 eastsound cd-e5 signature edition philodox's Profile: http://forums.slimdevices.com/member.php?userid=5061 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
philodox Wrote: > I actually sent the Brochure and Manual for the Digital Lens to Dan > Lavry for his opinion... and lets just say he doesn't have a high > opinion of what they are trying to sell. I'll take a look at that > link, thanks. :) It depends on how you look at the Digital Lens: As a 1990s device it was relevant in its time, but today the word length extension etc. is long subsumed by the functionality built into current SRC chips etc. and the quality of source clocks & clock recovery, in terms of both error & jitter, has improved greatly since its introduction. However, as a way (when it is suitably modified) of syncing any arbitrary source (that does not have a word-clock input) to a word clock (without modifying the source itself) the Digital Lens is a useful platform - thus during my progression from SLIMP3 though SB1 & SB2 to a SB3 I have not had to modify each of the four above to sync them to my dcs Purcell-Elgar-Verona stack, I have simply been able to plug each successive generation of SB into my modified Digital Lens ... -- reeve_mike reeve_mike's Profile: http://forums.slimdevices.com/member.php?userid=995 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
I actually sent the Brochure and Manual for the Digital Lens to Dan Lavry for his opinion... and lets just say he doesn't have a high opinion of what they are trying to sell. I'll take a look at that link, thanks. :) -- philodox box clever, watch your system come together crazy weather at the end of my tether ::る:: heavily modded akg k340 < xlr out < lavry *black* da10 > headphone out > john grado hf-1 slim devices squeezebox /\ ultimate power cell 200 eastsound cd-e5 signature edition philodox's Profile: http://forums.slimdevices.com/member.php?userid=5061 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
philodox Wrote: > That Genesis Digital Lens sounds like a really cool piece of kit. I > just read a few reviews on it... too bad it was discontinued in 2003. > Any ideas if there are other similar devices out there made by other > manufacturers? Altmann's boxes are said to do wonders to both sound and jitter :) , although I have no idea how much hype in it... http://www.jitter.de/ -- 325xi 325xi's Profile: http://forums.slimdevices.com/member.php?userid=5661 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
CarlOtto Wrote: > I think (my opinion, but I fully accept others having other views) SACD > is only marginally better than an upsampled CD. I agree that what you say is often the case, however, I find some of the 'pure' DSD releases from Telarc really something special ... -- reeve_mike reeve_mike's Profile: http://forums.slimdevices.com/member.php?userid=995 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
CarlOtto Wrote: > YHaven't got around to testing it properly though since I think (my > opinion, but I fully accept others having other views) SACD is only > marginally better than an upsampled CD. You are not alone with this opinion. You don´t even have to upsample. Sadly the CD layers or CD-Release regulary is mastered worse or clipping. Is this by accident? Don´t think so! -- Wombat Wombat's Profile: http://forums.slimdevices.com/member.php?userid=4113 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
reeve_mike Wrote: > Hi > > I have close to 500 SACDs so I am keeping mine :-) > > Mike You could of course rip them as wellbut it would take a serious amount of disk space. I've been thinking of simply feeding the Purcell (via the FireWire) the output from a SACD, then lifting that signal off the (single or dual) AES-EBU output from the Purcell (there is no copy protection in that format) - and feeding it into a professional sound card and simply record it. Haven't got around to testing it properly though since I think (my opinion, but I fully accept others having other views) SACD is only marginally better than an upsampled CD. -- CarlOtto CarlOtto's Profile: http://forums.slimdevices.com/member.php?userid=3581 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
That Genesis Digital Lens sounds like a really cool piece of kit. I just read a few reviews on it... too bad it was discontinued in 2003. Any ideas if there are other similar devices out there made by other manufacturers? -- philodox box clever, watch your system come together crazy weather at the end of my tether ::る:: heavily modded akg k340 < xlr out < lavry *black* da10 > headphone out > john grado hf-1 slim devices squeezebox /\ ultimate power cell 200 eastsound cd-e5 signature edition philodox's Profile: http://forums.slimdevices.com/member.php?userid=5061 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Hi CarlOtto Wrote: > > What I wonder here is - how did you get the wordclock sorted (is > someone doing this as an add-on?) and since I assume you could not get > balanced (AES-EBU) output from the SB3 - don't you then get a slightly > better sound via the Verdi connected with XLR to the DAC? > The set up is: - SB to a Genesis Digital Lens - I modded the Digital Lens to have a word clock input [actually a superclock, i.e. 256x] - one of the word clocks from the Verona is upped to a super clock using the Apogee Big Ben and fed the Digital Lens - output of Digital Lens to Purcell [what's frustrating is that the Purcell only has one AES input] CarlOtto Wrote: > I have had thoughts of selling the Verdi I have close to 500 SACDs so I am keeping mine :-) Mike -- reeve_mike reeve_mike's Profile: http://forums.slimdevices.com/member.php?userid=995 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
reeve_mike Wrote: > > > I have two sources: a SB & a dcs Verdi. > > For CD replay these feed a dcs Elgar+ via a dcs Purcell upsampler. > > The whole replay chain is synch'ed via a dcs Verona clock > (the SB path is modified to include a word clock input). > > If I have ripped a CD I play it via the SB; > not the Verdi, why would I ...? That is interesting - I have a very similar setup but I gave up on the Squeezebox used for transporting sound in any form, too many shortages (audiophile-wise). The things I really wanted to have were: 1) A word clock input on the SB 2) Balanced digital output And since I couldn't see myself hacking into the SB, I went for another solution: I got a professional sound card for PC with all the above included and I run a media PC (a silent build thing) with SoftSqueeze feeding the dCS system through the digital out from the soundcard. SoftSqueeze is then synchronized to a SB3 so I actually use the SB as a display and control unit. It works well, but with some minor irritating things like a very small gap between tracks due to the synch solution used. What I wonder here is - how did you get the wordclock sorted (is someone doing this as an add-on?) and since I assume you could not get balanced (AES-EBU) output from the SB3 - don't you then get a slightly better sound via the Verdi connected with XLR to the DAC? Quality-wise, I must say though that I just about never use the Verdi. Not even very often for SACD's since I feel that the quality from Red Book in the Slimserver-dCS system is so good, it's hardly worth the extra hassle for a minor increase (SACD). I have had thoughts of selling the Verdi - but then again, I'm probably not there yet. It feels strange to take the step to absolutely no CD-player. -- CarlOtto CarlOtto's Profile: http://forums.slimdevices.com/member.php?userid=3581 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Phil Leigh Wrote: > Yep - they are all square waves - with different m/s ratios but > certainly all square waves... OK, so that accounts for the confusion before. In any case the particular "square wave" you would get from SPDIF encoding a pure sine wave at 1 kHz will have a bump in its spectrum at 1kHz, because it's close to being exactly periodic with that frequency, and via correlated jitter that can affect what you hear. ekzdude Wrote: > > I just wanted to point out that square waves, although they have a > nominal frequency, are really composed of an infinite number of > sinusoidal signals. > Yeah, that's true. You can write my kind of square wave (meaning like the top image here http://en.wikipedia.org/wiki/Biphase_Mark_Code) as sq(t) = Sum[ (1/n) * sin(n t) ], where the sum is taken over odd integers n from 1 to infinity. If you truncate the sum because your scope can't resolve arbitrarily high frequencies, you get the kind of trace you're seeing there. And as you can see, the fundamental is the largest component, but all overtones are there too, just with less and less power as you go up. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
I just wanted to point out that square waves, although they have a nominal frequency, are really composed of an infinite number of sinusoidal signals. The edge of a "theoretical" square wave is an impulse with infinite frequency (i.e. vanishingly small period). I've attached a pic I took with my scope last weekend of a 24.576 MHz clock (crystal oscillator). Notice that even though my scope has 100 MHz bandwidth, it can't reproduce the edges. However, the fundamental frequency is obviously there. +---+ |Filename: scope.jpg| |Download: http://forums.slimdevices.com/attachment.php?attachmentid=1419| +---+ -- ezkcdude SB3->Derek Shek TDA1543/CS8412 NOS DAC->MIT Terminator 2 interconnects->Endler Audio 24-step Attenuators (RCA-direct)->Parasound Halo A23 125W/ch amplifier->Speltz anti-cables->DIY 2-ways + Dayton Titanic 10" subwoofer He's not hi-fi, he's my stereo. ezkcdude's Profile: http://forums.slimdevices.com/member.php?userid=2545 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Yep - they are all square waves - with different m/s ratios but certainly all square waves... -- Phil Leigh Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Loftprojection - Thanks for the support. :) I do hope that I can get my Squeezebox up to the level of my Eastsound with some of the mods that I have planned. [Considering thise - battery PSU; disconnect analog stage; maybe BNC connection] Not so that it can replace my Eastsound [I want a CD player as well], but so that it can become my main transport. Once I get it to this point I plan on ripping much more of my music and maybe getting one of those Nokia tablets to use as a fancy remote. :D -- philodox box clever, watch your system come together crazy weather at the end of my tether ::る:: heavily modded akg k340 < xlr out < lavry *black* da10 > headphone out > john grado hf-1 slim devices squeezebox /\ ultimate power cell 200 eastsound cd-e5 signature edition philodox's Profile: http://forums.slimdevices.com/member.php?userid=5061 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
ModelCitizen Wrote: > This is very interesting. > Can you confirm that my understanding of what you have said is correct? > You are saying that the SB analogue outs are less likely to be prone to > jitter than the digital outs coupled to an external DAC (even a > Benchmark Dac 1 for instance)? > MC Yes, that's what I'm saying, and I think it's true to within my (limited) understanding of this. Benchmark claims to be able to eliminate jitter via buffering and re-clocking, but it's not clear to me that this is possible and/or won't introduce other errors. Note that if that claim is true, all error-free (that is, decent) transports feeding a DAC 1 should be indentical, period. In any case, you should have less jitter at the input to the SB internal DAC than at the input to any external DAC. Of course that doesn't mean it will sound better, which is subjective and depends on lots of things besides jitter. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
a question about terminology - do you guys call all of these square waves, or only the top one? I would say only the top one, but maybe there's a different terminology in different fields: http://en.wikipedia.org/wiki/Biphase_Mark_Code By the way, that shows nicely how the clock and data are encoded in SPDIF. The bottom signal is the one that actually gets sent down the line (ideally). To see something perhaps closer to what really gets received by the DAC, see Figure 6 here: http://www.stereophile.com/reference/1093jitter/index1.html so you can see why there is jitter... -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
I think we are in danger of violently agreeing! the "rounding" does introduce uncertainty in the timing - so that's "jitter"... and yes what we need is an I2S feed from the SB into the DAC (or a master clock approach like dCS). I guess I'm in the minority in preferring the digital out of an SB2/3 to a spinning transport. The differences are MIGHTY small and "better" is a tough concept to pin down - everyone's mileage varies. Also, I'm not listening to the native SPDIF but a reclocked, decorrelated version. What I think is undeniable is the the SB is a more reliable/consistent transport - its bitstream from a given flac is ALWAYS the same...CDP's just aren't like that. Does anyone remember those early CDP's with error counters on them ? - I think meridian made one, and maybe Townsend? anyway, I notice they stopped making those pretty quickly... CD's do get damaged (even new ones can misread) and if it's a CD-ROM the computer will complain bitterly and the software won't work. However, red book will usually keep on playing it (albeit withi the wrong bits!). Also, lasers get worse with age and eventually fail... I know we are talking about jitter etc, but my view is that the SB is a more reliable/robust transport and for that I am grateful. As for sound quality - who knows? Personally I need the SPDIF to drive my TACT (it has no dacs/adcs). The RC has about a hundred times more impact on my enjoyment of the sound than the minor impacts of a little more/less jitter. And yes - if an audiophile SB with great PSU, DAC and the ability to do RC at least as good as the TACT were to come out I'd buy one instantly - almost regardless of price (!). But the RC capability would be mandatory otherwise I wouldn't bother. Actually, that would be a great product: one box, TACT or Lyngdorf or similar RC + SB + super DAC + suitable PSU's. The thing is no CDP could stand against that combo on subjective sound quality grounds without RC...and if it was all in one box/circuit, the jitter problem could be made to go away... ...and we could get back to just using the box for pure enjoyment of the music and exploring the backwaters of our collections (eyes mist over, reaches for the whisky bottle, ice clinks into glass, Roy Buchanan starts to play...) -- Phil Leigh Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
opaqueice Wrote: > > See above. About data rates, I totally agree - the problem is that > this digital audio standard sucks. There is a far better way to do > things - transmit all the data first, asynchronously with error > checking, to a big buffer sitting next to the DAC, and only then decode > using one dedicated clock. That would essentially eliminate jitter > (except that introduced by the original digitization of course). In > fact, the SB comes pretty close to doing that, at least until you hook > it up to an external DAC. This is very interesting. Can you confirm that my understanding of what you have said is correct? You are saying that the SB analogue outs are less likely to be prone to jitter than the digital outs coupled to an external DAC (even a Benchmark Dac 1 for instance)? MC -- ModelCitizen Squeezebox2 > Benchmark Dac1 > Naim NAC 82 > Naim NAP 250 > Shahinian Arcs. Music catalog: http://modelcitizen.mine.nu/music.txt ModelCitizen's Profile: http://forums.slimdevices.com/member.php?userid=446 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Phil Leigh wrote: > Robin - are you saying that you don't think jitter exists (in which > case, what does a jitter meter measure?) or that it does exist, but the > presence of jitter on the digital stream doesn't affect the performance > of the DAC? Neither. In fact, quite the opposite! R. ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
opaqueice wrote: > I totally agree - the problem is that > this digital audio standard sucks. There is a far better way to do > things - No argument here. The standard sucks. RedBook was designed without an expectations that microcontrollers and microprocessors would exist. Let alone that the entire 700 MB of data could fit easily into flash memory. But I see no probability that it will ever be fixed. The technology manufacturers take the failure of SACD and DVD-A as meaning that there is no future in better sound quality. And the mass acceptance of MP3, XM, Sirrius, etc. confirm that quality does not matter. Back to the topic, my SB2 to a Benchmark DAC-1 sounds great. I don't have a SB3 to compare it to. I used to have fairly high end CD players and the SB2/Benchmark sounds better and is imcomparably more convienent. I listen to more music. And that is all that matters. -- Pat http://www.pfarrell.com/music/slimserver/slimsoftware.html ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
pfarrell Wrote: > > Most of the understandable discussions of jitter talk about the > timing of the signal being wrong, not the rounding of the edges > of the signal. > Yes, but I think the reason there are timing errors is that the edges are not precisely well defined, due to rounding etc. So if you try to use them as a clock, your clock will have timing errors. > > For signal transmission, minor artifacts of rounding on > the edges of the square waves are ignored. > Probably you're thinking of asynchronous data transmission, where it only matters that you get the bits correct. Here, you have to get the bits correct from an isynchronous signal AND decode them at the right time. > > And audio frequences are very modest, > RedBook audio is defined as 16 bit stereo at 44.1k > = 176,400 bytes/second > = 172 Kbytes/second > > Digital signal rates in the gigahertz range are used all the time, > Megahertz is how you measure an original IBM PC. Red Book > audio is nothing. More than ten years ago, all the 'high end' > cd players did 16 times oversampling, which still has > the data rate at about 2 megabits/second. > > If there is a problem, it isn't caused by rounding of > the square waves used for signaling. > See above. About data rates, I totally agree - the problem is that this digital audio standard sucks. There is a far better way to do things - transmit all the data first, asynchronously with error checking, to a big buffer sitting next to the DAC, and only then decode using one dedicated clock. That would essentially eliminate jitter (except that introduced by the original digitization of course). In fact, the SB comes pretty close to doing that, at least until you hook it up to an external DAC. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
I've been reading this thread with great interest because I don't own a SB yet but I'm very interested by it. Anyway, in my opinion, I think the most relevant piece of information here is what Philodox posted. He has a real life experience where his Eastsound CDP used as a transport into a DAC actually sounds better than his SB3 into the same DAC. Did he do a blind test, I don't know, but I guess we can trust that he did a "relatively objective" test since he owns both piece of equipment. To me, it would be really interesting if more people would post the real tests they did to verify is the SB3 digital out produces or not equal, higher or lower sound quality then high end CDP used as transports. The original poster was asking about a SB3 into a high end DAC versus a high end CDP, that would be not an objective test because the DAC in the CDP can be of lower or higher quality then the DAC used with the SB. However a high end CDP as transport into the same DAC used with the SB3 digital out produces a real "objective" test, like what Philodox did. Up to now, most of the "relatively objective" tests (magazine articles and forum threads) that I've read were pointing to the same conclusion as what Philodox said. Using a high end CDP as transport into a high end DAC and high end downstream system produces a "slightly" better sound quality then using the SB3 as transport. Is the SB3 an incredible bargain transport, sure. Is the SB3 an incredible high end transport, not quite it seems. -- Loftprojection Loftprojection's Profile: http://forums.slimdevices.com/member.php?userid=5525 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
opaqueice wrote: > As I understand it, that rounding is the cause of jitter. A (basic) > DAC uses rising or falling edges as a clock, but since as you say those > edges aren't very well defined that introduces errors. If the DAC used > its own clock, since that will not be exactly in sync with the > transport's clock it will either fall behind or get ahead, causing > errors eventually as it starts to read the wrong bit. Same problem > with a buffer, unless it's really really big I guess... Most of the understandable discussions of jitter talk about the timing of the signal being wrong, not the rounding of the edges of the signal. For signal transmission, minor artifacts of rounding on the edges of the square waves are ignored. And audio frequences are very modest, RedBook audio is defined as 16 bit stereo at 44.1k = 176,400 bytes/second = 172 Kbytes/second Digital signal rates in the gigahertz range are used all the time, Megahertz is how you measure an original IBM PC. Red Book audio is nothing. More than ten years ago, all the 'high end' cd players did 16 times oversampling, which still has the data rate at about 2 megabits/second. If there is a problem, it isn't caused by rounding of the square waves used for signaling. -- Pat http://www.pfarrell.com/music/slimserver/slimsoftware.html ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
The DAC chip itself is not the main cause of jitter. The main cause of jitter is from the transport (or SB3 in this case) and the SPDIF receiver. That is why there are quite a few folks who bypass the receiver by using separate clock signals. There's a thread about this over in the DIY section, started by John Swenson. He built his own DAC and taps the I2S signal directly from the SB3. It's a great idea, but of course, you need a lot of DIY know-how. There are other ways to cut down jitter, such as asynchronous re-sampling, but that involves some digital manipulation of the original signal. For that reason, a bunch of folks are opposed to that (not me). -- ezkcdude SB3->Derek Shek TDA1543/CS8412 NOS DAC->MIT Terminator 2 interconnects->Endler Audio 24-step Attenuators (RCA-direct)->Parasound Halo A23 125W/ch amplifier->Speltz anti-cables->DIY 2-ways + Dayton Titanic 10" subwoofer He's not hi-fi, he's my stereo. ezkcdude's Profile: http://forums.slimdevices.com/member.php?userid=2545 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
CardinalFang Wrote: > > What is the process by which a modern DAC samples the input? Does it go > by voltage measurements at fixed intervals or is there an inbuilt > "clocking" mechanism that causes the buffering of bits? Of course I > shouldn't be so lazy and should go find out for myself! > Paul As I understand it, that rounding is the cause of jitter. A (basic) DAC uses rising or falling edges as a clock, but since as you say those edges aren't very well defined that introduces errors. If the DAC used its own clock, since that will not be exactly in sync with the transport's clock it will either fall behind or get ahead, causing errors eventually as it starts to read the wrong bit. Same problem with a buffer, unless it's really really big I guess... -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Phil Leigh Wrote: > > These changes to the timing of the transitions may be random, periodic > (eg related to an AC frequency elsewhere in the circuit such as the > mains) or correlated to the music because of the DAC analogue stage > impacting something in the clocking/clock recovery chain via the PSU > rails for example. > Apparently there is another mechanism besides the one you mention here by which jitter can be correlated to the music, and that is what I've been trying (and evidently totally failing!) to describe. It's that the isynchronous digital voltage signal itself contains some frequency components which are related to the spectrum of the original analogue signal that was digitized. Given that some jitter is "correlated", meaning the timing errors you mentioned are not random but instead are influenced by the digital signal itself, this means some of the jitter spectrum will be correlated to the original music (and some won't). -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Phil Leigh Wrote: > erm, guys... > > a perfect square wave can by definition only have 2 DC values with an > instantaneous transition between them (of course this is not possible > in the real world but we can get pretty close to perfect) with a > (variable or fixed) mark/space ratio determining the > periodicity/instant of the transition. I have never looked at the output from a transport or the SB on a scope, but the last time a looked at a digital signal, it was far from square. The leading and trailing edges were rounded and suffered from digital noise, so detecting the actual point at which a signal changes state was almost abitrary. Now this was from looking at TTL, so I'm assuming that it is different for a digital output - or is it? What is the process by which a modern DAC samples the input? Does it go by voltage measurements at fixed intervals or is there an inbuilt "clocking" mechanism that causes the buffering of bits? Of course I shouldn't be so lazy and should go find out for myself! Paul -- CardinalFang You're only young once, but you can be immature forever... CardinalFang's Profile: http://forums.slimdevices.com/member.php?userid=962 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
erm, guys... a perfect square wave can by definition only have 2 DC values with an instantaneous transition between them (of course this is not possible in the real world but we can get pretty close to perfect) with a (variable or fixed) mark/space ratio determining the periodicity/instant of the transition. Jitter does not change the 2 DC values - it changes the apparent exact moment in time when the transition takes place. Even if the DC values did change slightly because of poor PSU regulation/decoupling, they'd still represent a (logical) zero or one to the recipient, unless they went wildy out of tolerance. These changes to the timing of the transitions may be random, periodic (eg related to an AC frequency elsewhere in the circuit such as the mains) or correlated to the music because of the DAC analogue stage impacting something in the clocking/clock recovery chain via the PSU rails for example. Anything in the DAC chain that can alter the analogue output AND that relies on knowing exactly when the transition is supposed to take place is thus in jeopardy from jitter. Jitter can be introduced by any transport - this can be removed - maybe completely - or at least ameliorated just before or just inside the DAC. However, lots of CD's are in fact created from jittery digital masters/multi-tracks - and this can't be removed at home!. Thankfully this problem has more or less gone nowadays... There is another corruption mechanism (not jitter) that intermittantly mangles the square wave so that it is harder to detect the transition point in the receiver - or even that a transition has occurred. The resultant bitstream has unrecoverable (but possibly interpolatable) errors - this is the damaged cellphone/sat TV/CD dropout syndrome... Robin - are you saying that you don't think jitter exists (in which case, what does a jitter meter measure?) or that it does exist, but the presence of jitter on the digital stream doesn't affect the performance of the DAC? -- Phil Leigh Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
OK, I will take this point by point... Robin Bowes Wrote: > > I'm afraid you are wrong in so many ways. > If so, I'm happy to learn something. > > A digital signal does not have periodicity - it is just a stream of > bits. It is sent over analogue transmission paths as a square wave. > In this case it *is* periodic, as you can see from my example of the digitized sine wave. I think perhaps there is a confusion about the term square wave - to me that means simply a signal which oscillates from one level to the other, with sharp transitions, and with a fixed exact periodicity. That of course contains zero information - at best it corresponds to one particular stream of bits. A general digital signal oscillates back anf forth, but it is something like 0111000101010011 or whatever, and is square only in the sense that the voltage takes two values only. > > The receiver of the signal decodes the square-wave signal and also > extracts the timing information from the same signal. > > As Pat as already pointed out, jitter is caused by errors in detecting > the transition between 1 and 0 in the square wave in the analogue > domain, which causes timing errors. So, the space between samples > varies > from the "standard" (for 44.1kHz sample rate)1/1,411,200 of a second. > This means that the analogue signal reconstituted from the digital > signal has different frequency content than the original input signal. > R. Yes, that is the basic point about jitter. What I thought we were discussing is HOW the analogue signal you end up with differs from the original. In other words, what is the spectrum of the "noise" - the extra stuff which has been added by jitter? Your original claim (perhaps I misunderstood you) was that that spectrum is determined by the original music. It turns out that claim is partly correct, as I was trying to explain. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
pfarrell Wrote: > > This is flat not true. It is not like a square wave, it is a square > wave. And there is no tone to it, you don't listen to the digital > signal > you listen to the analog signal after it has been processed by the > DAC. > It is *not* a square wave, because not all the bits are the same, or 01010101..., or whatever. It's square only in the sense that it has two possible voltage levels (ideally). Its spectrum (by which I mean its Fourier transform) is not simply the spectrum of a simple square wave (whose spectral composition is (1/n)sin(n), for n odd), but should be closer to that than to the spectrum of a sine wave (which is simply a spike at one frequency). However, there will be a spike at 1 KHz in this case, which was the point. Nobody is suggesting you "listen" to this - perhaps you should go back and read the discussion before this and see why the topic of the spectrum of the digital signal is interesting. It's because the jitter spectrum can be correlated with the digital signal spectrum, and you (might) hear the jitter spectrum after D->A. There's an excellent picture illustrating how this can happen in the the reference I gave a few posts back. > > I see no grounding for this claim at all in this piece. > > I don't know why you are using the "word" (if it is even a word) > anharmonic, when the signals you are describing are harmonics or > beats. > They are present in any signal. Look up the phrases > "harmonic distortion" and "intermodulation distortion" > I'm not sure what claim you're referring to. The point here is that some of the frequencies present in this spectrum are unrelated to the harmonic content of the original 1 kHz sine wave, for example the peak at 100 Hz which is present in my example above. By "anharmonic" (which by the way is a commonly used term, in physics at least) I mean "not an integer multiple of the dominant tone" in the music, 1 kHz in this case. These anharmonic frequency components arise for example from beating between the original frequency in the music and the quantization frequency (44100), and according to several authors are what makes jitter so unpleasant to listen to. Contrary to your assertion, such effects would _not_ normally be present in an analogue signal, because there is no such other frequency for the signal to beat against. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
opaqueice wrote: > OK, in case anyone cares, here's a (hopefully correct) explanation of > how some components of jitter can be correlated with the frequency > components of the analogue audio signal. [snip] I'm afraid you are wrong in so many ways. A digital signal does not have periodicity - it is just a stream of bits. It is sent over analogue transmission paths as a square wave. The receiver of the signal decodes the square-wave signal and also extracts the timing information from the same signal. As Pat as already pointed out, jitter is caused by errors in detecting the transition between 1 and 0 in the square wave in the analogue domain, which causes timing errors. So, the space between samples varies from the "standard" (for 44.1kHz sample rate)1/1,411,200 of a second. This means that the analogue signal reconstituted from the digital signal has different frequency content than the original input signal. R. ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
opaqueice wrote: > OK, in case anyone cares, here's a (hopefully correct) explanation of > how some components of jitter can be correlated with the frequency > components of the analogue audio signal. I for one would love a correct explaination about jitter and how it is a problem. From what I can tell, it is mostly a 'problem' that is solved by high priced audiophile products. > [Snip] > just like the sine wave, but its spectrum will be something complicated > with lots of harmonic overtones and a huge peak at 44000 Hz (and > probably 16*44000 too), because it's very far from a pure tone (it's > something more like a square wave). This is flat not true. It is not like a square wave, it is a square wave. And there is no tone to it, you don't listen to the digital signal you listen to the analog signal after it has been processed by the DAC. Jitter, if it is a problem, is related to the edges of the square wave not being at the right place in time, causing the signal to be mis-interpreted. > from remembering about beating frequencies. So you now have lots of > anharmonic frequency components (100 Hz, 900 Hz, 1100 Hz, etc) in there > as well (and you'll still have a peak at 1 kHz, but probably smaller), > and apparently that's the really nasty sounding part. I see no grounding for this claim at all in this piece. I don't know why you are using the "word" (if it is even a word) anharmonic, when the signals you are describing are harmonics or beats. They are present in any signal. Look up the phrases "harmonic distortion" and "intermodulation distortion" -- Pat http://www.pfarrell.com/music/slimserver/slimsoftware.html ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
OK, in case anyone cares, here's a (hopefully correct) explanation of how some components of jitter can be correlated with the frequency components of the analogue audio signal. Suppose you digitize a 1 kHz sine wave with 16 bit at 44000 Hz (I know the CD standard is 44.1 kHz; more on that in a second). That means every 1/44000 of a second, you measure the level, turn it into a sequence of 16 bits, and send it out. After 44 such sequences you're back to where you started in the sine wave, since 44 * 1 kHz = 44000 Hz. So the digital signal will have an exact periodicity of 1 kHz, just like the sine wave, but its spectrum will be something complicated with lots of harmonic overtones and a huge peak at 44000 Hz (and probably 16*44000 too), because it's very far from a pure tone (it's something more like a square wave). However in real life (where the numbers are less carefully chosen) the situation is actually more complicated. Suppose you have that same 1 kHz sine wave, but the sample frequency is 44100 Hz rather than 44000. Then the (exact) periodicity of the digital signal is actually 100 Hz, not 1 kHz. You can see why that is if you think about it a bit, or from remembering about beating frequencies. So you now have lots of anharmonic frequency components (100 Hz, 900 Hz, 1100 Hz, etc) in there as well (and you'll still have a peak at 1 kHz, but probably smaller), and apparently that's the really nasty sounding part. So far I haven't mentioned jitter per se; the last piece to this is that apparently some of the jitter is correlated with the digital signal spectrum, and so that will pick up all this junk and pass it one into the analogue domain after D/A conversion, making your ears hurt. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
I think you'll find that its the correlated jitter that is the problem - in the same way that level-related noise pumping is really annoying with DBX companding, whereas Dolby (B) is just dull...(sorry - best analogy I could come up with). The uncorrelated (to the music) jitter is less intrusive - hence the "jitter scrambling" techniques of Altmann et al... Now this could all be hokum...but I'd swear that it makes a positive difference in my system. I don't have access to any high-end CDP's anymore (sold them all!) so it's hard for me to compare, but I am 110% positive that the SB2 (& 3) is a better transport than all of the ones I've owned/tried in the including some pretty funky esoterica! BUT - and its a big but - this was all tested over several months with the Altmann JISCO & UPCI in the chain (SB-TACT-"altmann boxes"-DAC) vs CDP-"altmann boxes"-DAC - nothing else was changed in the system although lots of CDP's (Linn, Naim, Chord, Meridian) and a few DACS were tried (dCS, Chord, MF etc) Also the differences (as a transport) were very small - maybe non-existant in some cases. As I'd already bought the altmann boxes, I never tested what happend if I pulled them out of the chain. It's possible that these little boxes were eliminating the differences in the transports? -- Phil Leigh Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
OK, I had a chance to check on this a little more, and there apparently _is_ an effect where the jitter spectrum can have a peak correlated to the analogue signal frequency. Apparently this happens mostly when the jitter is due to bandwidth limitations in the transmission line, and will be in addition to many other non-harmonic frequencies which are correlated with such things as the 44.1 kHz digital frequency etc. I guess this is due to the fact that, for example, a 1 kHz pure sine wave encodes into a digital sequence which itself has some periodicity at 1 kHz. I couldn't tell how important that is for music, but everything I read seemed to agree that the worst (for audio) type of jitter are the components which are not harmonically related to the signal. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Phil Leigh Wrote: > Can I suggest that you/we read up on correlated vs. uncorrelated jitter > as they are different beasts... > >From what I understand, the word "correlated" refers in this context to any non-random effect on the jitter spectrum, for example an effect which is correlated with the signal itself. However the signal in question here is the digital signal, not the analogue one, and hence the spectrum of correlated jitter (at least in the discussions I've seen of it) has nothing to do with the music. See for example the third page of this: http://www.analogzone.com/tmt_0516.pdf Again, I suppose it is logically possible for the analogue part of the audio chain to interfere with the digital part and induce jitter correlated with the music, but I have not seen that mentioned anywhere. By the way "uncorrelated" here means random (somewhat loosely defined), for example gaussian thermal noise or power supply interference. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Phil Leigh Wrote: > Philodox - what I am saying is that bass solidity (well defined, easy to > listen to) is easily damaged by jitter. One of the most commonly heard > improvements is "better" bass when jitter is significantly reduced.Oh, I see > what you are saying now. I thought you were implying that my Eastsound was *more* jittery and was causing the bass become more defined. :D I would expect the same. I mean, as long as the CD player reads the disc properly it has the same data as my FLAC files. At that point all that matters is getting that data to my DAC so that it can work it's magic. Apparently my Eastsound does a better job of this than my Squeezebox. Trust me, I was surprised to hear a difference as well. I was not going into this thinking the Squeezebox would be bested as a transport. ;) -- philodox box clever, watch your system come together crazy weather at the end of my tether ::る:: heavily modded akg k340 < xlr out < lavry *black* da10 > headphone out > john grado hf-1 slim devices squeezebox /\ ultimate power cell 200 eastsound cd-e5 signature edition philodox's Profile: http://forums.slimdevices.com/member.php?userid=5061 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Can I suggest that you/we read up on correlated vs. uncorrelated jitter as they are different beasts... Philodox - what I am saying is that bass solidity (well defined, easy to listen to) is easily damaged by jitter. One of the most commonly heard improvements is "better" bass when jitter is significantly reduced. -- Phil Leigh Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Robin Bowes Wrote: > opaqueice wrote: > > Robin Bowes Wrote: > >> Please read up on what jitter is and how it can and does have a > >> spectrum > >> related to the music. > >> > > > > I have read quite a lot, and I think I have a decent understanding > of > > jitter. Nothing I have read has indicated that the jitter spectrum > > should be harmonically related to the original analogue signal. On > the > > contrary, many people mention specifically that it is not, and cite > that > > as the reason jitter sounds so bad. Here's an excellent example: > > > >> These sidebands around the signal being decoded aren't harmonically > >> related to the signal, making them particularly unpleasant. > > > > from http://www.stereophile.com/reference/1093jitter/ . I recommend > > you take a look at figure 4 of that reference, and then explain to > me > > how the spectrum of that noise has anything whatsoever to do with > the > > harmonic content of the music. > > Please read what I actually wrote. > Well, actually I did read what you wrote, and just did again... and again, I ask you - why would jitter "have a spectrum related to the music" as you claim? Maybe this exchange would be more interesting if you would actually back up what you're claiming. I'm not saying this can't happen, and I'm certainly not an expert on this, but I've never read anything which says this - in fact just the contrary. Furthermore it makes little sense logically, unless perhaps there is some effect where the analogue part of the audio path induces jitter in the digital signal. reeve_mike Wrote: > > The above statement refers specifically to the numbers in the example > given in the text. > > If one chose the right numbers one could make them related, see the > formula in Footnote 5 of the article. > Of course they could be related coincidentally, but it would be just that - coincidence. It's as someone said earlier, like claiming getting a book wet would obscure only the R's and no other letters... I agree about subjectivity, but I think one can learn a lot examining possible causes for what people hear. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
opaqueice wrote: > Robin Bowes Wrote: >> Please read up on what jitter is and how it can and does have a >> spectrum >> related to the music. >> > > I have read quite a lot, and I think I have a decent understanding of > jitter. Nothing I have read has indicated that the jitter spectrum > should be harmonically related to the original analogue signal. On the > contrary, many people mention specifically that it is not, and cite that > as the reason jitter sounds so bad. Here's an excellent example: > >> These sidebands around the signal being decoded aren't harmonically >> related to the signal, making them particularly unpleasant. > > from http://www.stereophile.com/reference/1093jitter/ . I recommend > you take a look at figure 4 of that reference, and then explain to me > how the spectrum of that noise has anything whatsoever to do with the > harmonic content of the music. Please read what I actually wrote. >> The file won't get corrupted in transfer - or at least, if it does, >> you'll know about it. That's what the error correction is for. >> >> > > Files of course _do_ get corrupted in transfer occasionally. However, > if you refuse to discuss this analogy there are many others - for > example the distortion you hear over a digital cell phone, or the image > distortion you sometimes see on TV from a bad digital satellite feed, or > take your pick. Again, please read what I actually wrote. The effect of jitter is much more subtle than any of the other examples you give. R. ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
opaqueice Wrote: > I'm afraid you fall into Phil's category 1, hence helping prove his > point ;-).I can turn that around pretty easily. People who can't accept that > high end transports make a difference... don't own them. :popaqueice Wrote: > But seriously, and I ask this in a spirit of friendly skepticism, how > can digital errors (either jitter or missed bits) change something like > bass detail? The bits themselves have essentially nothing to do with > bass, until they get decoded through a very complex process in the DAC.No > idea, but it is a common observation. When I first got a high end CD player I didn't even have a decent amp yet... hooked it up to an all in one portable DAC/Amp that I had and there was a huge difference over my AV320 which was outputting WAV files. I don't bother trying to figure out why I hear what I hear. I trust my ears. :)opaqueice Wrote: > To make an analogy, since you're a network engineer isn't it kind of > like saying when you send a jpeg file over a wireless net versus wired > the reds in the image are more washed out and less saturated, but the > greens and blues are fine? > > EDIT - to make my analogy a bit better, suppose one of the files was > corrupted slightly, but the image was still viewable...Ummm... sorry, that > analogy seems to make sense on the surface, but these are two completely different things. What people seem to forget is that regardless of the DATA you are starting with, the method by which your transport 'transports' the data to your DAC is the important part... as long as it does its job in first retrieving the data. [Which any decent player will] -- philodox box clever, watch your system come together crazy weather at the end of my tether ::る:: heavily modded akg k340 < xlr out < lavry *black* da10 > headphone out > john grado hf-1 slim devices squeezebox /\ ultimate power cell 200 eastsound cd-e5 signature edition philodox's Profile: http://forums.slimdevices.com/member.php?userid=5061 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
opaqueice Wrote: > > "These sidebands around the signal being decoded aren't harmonically > related to the signal, making them particularly unpleasant." > The above statement refers specifically to the numbers in the example given in the text. If one chose the right numbers one could make them related, see the formula in Footnote 5 of the article. However, I agree that it is hard to believe that specific frequencies will be systematically affected at all times for any music in a particular system ... BTW take a look at the dcs AES paper on the subjective effects of high sample rates and bit depths, can time smear really explain the perceived bass benefits of increased sample rates ...? At the end of the day, audio, like anything else involving the senses, is too subjective for absolute statements :-O But, as a scientist, it's fun trying to find explanations ... :-) -- reeve_mike reeve_mike's Profile: http://forums.slimdevices.com/member.php?userid=995 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Robin Bowes Wrote: > > Please read up on what jitter is and how it can and does have a > spectrum > related to the music. > I have read quite a lot, and I think I have a decent understanding of jitter. Nothing I have read has indicated that the jitter spectrum should be harmonically related to the original analogue signal. On the contrary, many people mention specifically that it is not, and cite that as the reason jitter sounds so bad. Here's an excellent example: > > These sidebands around the signal being decoded aren't harmonically > related to the signal, making them particularly unpleasant. from http://www.stereophile.com/reference/1093jitter/ . I recommend you take a look at figure 4 of that reference, and then explain to me how the spectrum of that noise has anything whatsoever to do with the harmonic content of the music. > > > The file won't get corrupted in transfer - or at least, if it does, > you'll know about it. That's what the error correction is for. > > Files of course _do_ get corrupted in transfer occasionally. However, if you refuse to discuss this analogy there are many others - for example the distortion you hear over a digital cell phone, or the image distortion you sometimes see on TV from a bad digital satellite feed, or take your pick. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Robin Bowes Wrote: > > Please read up on what jitter is and how it can and does have a > spectrum > related to the music. > To follow Robin's advice, here is a much quoted good place to start: http://www.stereophile.com/reference/1093jitter/index.html And note the distinction between on the one hand the causes of jitter and on the other hand the impact of the jitter on the audio signal ... Mike -- reeve_mike reeve_mike's Profile: http://forums.slimdevices.com/member.php?userid=995 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
All I was saying is that bass "solidity" (timing?) is affected by jitter (IMHO). I think we humans are quite sensitive to timing errors in lower frequencies - it's just a theory, nothing more. There is an audible difference in correlated vs. uncorrelated jitter... IME jitter is responsible for most (maybe all?) of the core problems with digital reproduction. I've tried higher sampling rates/bit depths extensively in studio conditions and whilst there are improvements to be had IMHO they are NOT critical. I'm not convinced we really understand the science behind all of this...however, jitter is definitely audible to me. It manifests itself to me as indistinct bass and vague treble and I get a headache after 30 mins or so... ymmv. In my system I can listen for 12 hours+ with NO stress. It is not the best system in the world (by any measure) but it does some things OK. -- Phil Leigh Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
opaqueice wrote: > Robin Bowes Wrote: >> It's the timing information that is the issue. This has been covered on >> these formums many times. >> > > There are (at least) two problems which could occur; one is timing > (jitter) and the other is simply bad bits. I think it's impossible for > bad bits to have an effect like changing the bass. But even for jitter, > it seems rather unlikely, since the spurious sounds introduced by jitter > will have a spectrum which has absolutely nothing to do with the music. > They are due to reflections in the cable, interference from the power > supply, maybe your neighbor running his dishwasher - but it's nothing > at all to do with the frequency spectrum of the music itself (unlike > analogue, where there are many frequency dependent effects). Please read up on what jitter is and how it can and does have a spectrum related to the music. >> No, it's not the same at all. >> >> Network transmission has error correction. The data is wrapped up in >> various layers of protocols. >> >> With digital audio, the bits simply transmitted over an analogue >> medium. >> There are all sorts of ways the signal can degrade in transmission and >> hence the musical information represented by the signal can be >> affected. >> >> R. > > I agree, it's not a very good analogy - so suppose instead the file > gets corrupted in transfer, then the same question. The file won't get corrupted in transfer - or at least, if it does, you'll know about it. That's what the error correction is for. You don't have that luxury in digital audio. R. ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Robin Bowes Wrote: > > It's the timing information that is the issue. This has been covered on > these formums many times. > There are (at least) two problems which could occur; one is timing (jitter) and the other is simply bad bits. I think it's impossible for bad bits to have an effect like changing the bass. But even for jitter, it seems rather unlikely, since the spurious sounds introduced by jitter will have a spectrum which has absolutely nothing to do with the music. They are due to reflections in the cable, interference from the power supply, maybe your neighbor running his dishwasher - but it's nothing at all to do with the frequency spectrum of the music itself (unlike analogue, where there are many frequency dependent effects). > > > No, it's not the same at all. > > Network transmission has error correction. The data is wrapped up in > various layers of protocols. > > With digital audio, the bits simply transmitted over an analogue > medium. > There are all sorts of ways the signal can degrade in transmission and > hence the musical information represented by the signal can be > affected. > > R. I agree, it's not a very good analogy - so suppose instead the file gets corrupted in transfer, then the same question. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Robin Bowes Wrote: > > No, it's not the same at all. > > Network transmission has error correction. The data is wrapped up in > various layers of protocols. > > With digital audio, the bits simply transmitted over an analogue > medium. > There are all sorts of ways the signal can degrade in transmission and > hence the musical information represented by the signal can be > affected. > > R. I think his point is just that, if an error were to happen, it wouldn't make sense for it to only happen to certain colors. Every bit is equally open to corruption. It would be like drenching a book in water and giving to someone, only to have them complain that all the R's were missing. That being said, I could buy that perhaps the corruption could cause a lack of "bass solidity". Going back to the JPEG example, the corruption might exist throughout the entire photo but be *easier to see* in areas that are solid black, but less noticeable in more "busy" sections of the image. -- azinck3 azinck3's Profile: http://forums.slimdevices.com/member.php?userid=3967 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
opaqueice wrote: > philodox Wrote: >> I use both my Squeezebox 3 and my Eastsound CD-E5 as transports to my >> Lavry Black DA10. The Eastsound is noticably better as a transport. > > I'm afraid you fall into Phil's category 1, hence helping prove his > point ;-). > > But seriously, and I ask this in a spirit of friendly skepticism, how > can digital errors (either jitter or missed bits) change something like > bass detail? The bits themselves have essentially nothing to do with > bass, until they get decoded through a very complex process in the DAC. It's the timing information that is the issue. This has been covered on these formums many times. > To make an analogy, since you're a network engineer isn't it kind of > like saying when you send a jpeg file over a wireless net versus wired > the reds in the image are more washed out and less saturated, but the > greens and blues are fine? No, it's not the same at all. Network transmission has error correction. The data is wrapped up in various layers of protocols. With digital audio, the bits simply transmitted over an analogue medium. There are all sorts of ways the signal can degrade in transmission and hence the musical information represented by the signal can be affected. R. ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Phil Leigh Wrote: > > I'm wondering if Philodox is hearing jitter...bass "solidity" is one of > the victims of jitter IMHO... Can you eleborate on that? I've heard a few examples of (intentionally) jittered sound files (with MUCH more jitter added than the SB or any decent source should), and they sounded pretty bad, but I didn't notice that the bass was particularly affected. More like some extra non-harmonic frequencies in there; really unpleasant to listen to. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
flac jacket - very funny (ROTFLMHO) I too can hear NO difference between coax (expensive Kimber Silver one) and toslink (middling quality) in my particular system - but I'm happy to believe that others will hear differences in their systems. I'm wondering if Philodox is hearing jitter...bass "solidity" is one of the victims of jitter IMHO...I do think there is mileage in trying to get rid of jitter on the SPDIF/toslink i/f. My argument was about the transport of the "bitstream" to the output of the SB..not about what happens next. As a case in point (and with due deference to Sean!) I do think that the sound can be "improved" by removing jitter just before (or within) the DAC. Phil (kevlar upgraded to chain mail - old technology, but good reviews (5 maces) in "What Armour") -- Phil Leigh Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Phil Leigh Wrote: > > Until you try and turn them into sound, bits are indeed bits... There > are many reasons why an accurate rip to HD will give a reliably (ie > repeatably) accurate rendition of the right bits in the right order - > and why even the BEST CDP in the world (whatever that is) will sometime > misread bits from a spinning disc... > No Kevlar jacket required for the above, it's a fact! [Although some of the latest CDPs which use ROM drives and do multiple reads will be less prone to occasionally delivering bad data ...] I have two sources: a SB & a dcs Verdi. For CD replay these feed a dcs Elgar+ via a dcs Purcell upsampler. The whole replay chain is synch'ed via a dcs Verona clock (the SB path is modified to include a word clock input). If I have ripped a CD I play it via the SB; not the Verdi, why would I ...? -- reeve_mike reeve_mike's Profile: http://forums.slimdevices.com/member.php?userid=995 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
philodox Wrote: > I use both my Squeezebox 3 and my Eastsound CD-E5 as transports to my > Lavry Black DA10. The Eastsound is noticably better as a transport. I'm afraid you fall into Phil's category 1, hence helping prove his point ;-). But seriously, and I ask this in a spirit of friendly skepticism, how can digital errors (either jitter or missed bits) change something like bass detail? The bits themselves have essentially nothing to do with bass, until they get decoded through a very complex process in the DAC. To make an analogy, since you're a network engineer isn't it kind of like saying when you send a jpeg file over a wireless net versus wired the reds in the image are more washed out and less saturated, but the greens and blues are fine? -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Phil Leigh Wrote: > > > The only people who don't accept that an accurate rip+HD will > outperform a high-end CDP as a digital transport are: > > 1) people who (currently) own high-end CDP's > 2) hi-fi reviewers > 3) buffoons who know nothing about how computers work. (Pat, this isn't > a reference to you!) > > Phil (kevlar jacket enabled) While I too salute your bravery, in this particular forum I'm not sure you'll really need the flac jacket... on the issue of digital transports, an experiment anyone with an external DAC can do easily is compare Toslink to coax. Many DACS have an input selector switch, so try comparing (say) a cheap plastic Toslink cable to high quality coax. I've tried that, and I didn't hear any difference in my system. This is relevant because Toslink should (at least according to some DSP engineers) induce lots of jitter relative to coax - probably much more of a difference than between two good-quality digital transports such as SB and CD player. Apparently in my case it wasn't enough to make an audible difference. And of course (here I go again!) please do this blind if you think you can hear a subtle difference... -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Phil Leigh Wrote: > The only people who don't accept that an accurate rip+HD will outperform > a high-end CDP as a digital transport are: > > 1) people who (currently) own high-end CDP's > 2) hi-fi reviewers > 3) buffoons who know nothing about how computers work.I use both my > Squeezebox 3 and my Eastsound CD-E5 as transports to my Lavry Black DA10. The Eastsound is noticably better as a transport. I am also a network administrator, and I know about all of the little audiophile tricks to get good sound out of a computer system. With the squeezebox being electrically seperate from the computer you would assume that it should be just as good. Whatever the reason, this is not the case. Bass is much better defined on the Eastsound and there is more clarity overall. Now, I still use my Squeezebox a lot of the time as it is one hell of a fun toy... but until I address these issues I will be sticking with my Eastsound for critical listening. Perhaps a battery PSU for the Squeezebox will even out the playing field. ;) -- philodox box clever, watch your system come together crazy weather at the end of my tether ::る:: heavily modded akg k340 < xlr out < lavry *black* da10 > headphone out > john grado hf-1 slim devices squeezebox /\ ultimate power cell 200 eastsound cd-e5 signature edition philodox's Profile: http://forums.slimdevices.com/member.php?userid=5061 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
I tip my hat to Phil and his brave display of logic :) -- radish radish's Profile: http://forums.slimdevices.com/member.php?userid=77 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Until you try and turn them into sound, bits are indeed bits...and one day someone will devise an experiment to prove this. There are many reasons why an accurate rip to HD will give a reliably (ie repeatably) accurate rendition of the right bits in the right order - and why even the BEST CDP in the world (whatever that is) will sometime misread bits from a spinning disc... In the world of SPDIF/Toslink, even with the correct bits, what matters is jitter messing up the "timing of the bits" and of course the filtering and final analogue stage of the DAC. The clocking and cabling play a part in all of this, as does PSU noise and interference. caution - sweeping generalization alert :o) The only people who don't accept that an accurate rip+HD will outperform a high-end CDP as a digital transport are: 1) people who (currently) own high-end CDP's 2) hi-fi reviewers 3) buffoons who know nothing about how computers work. Phil (kevlar jacket enabled) -- Phil Leigh Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
opaqueice Wrote: > > If you were using the CD player as a digital transport (i.e. sending > its digital out into the same DAC as the SB) I think the SB will > probably win or tieThat's not my experience - good though the SB3 is, it just > isn't as good as the best transports. In theory, the SB should be capable of being at least as good as any CDP. But in practice, it's generally down to the detail and quality of the actual implementation (in both cases). -- Patrick Dixon www.at-tunes.co.uk Patrick Dixon's Profile: http://forums.slimdevices.com/member.php?userid=90 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 + high end DAC versus high end CD Player?
Mike Anderson Wrote: > For sound quality, how would you compare the SB3 running into a high end > DAC with a high end CD player? > > I'm having a debate with someone who thinks you simply can't beat a top > quality CD player, no matter how good your DAC is. > > I'm not an engineer, but I can't imagine why this would be the case, > assuming you've got error-free rips of your CDs. > > Can any engineers or technophiles address this issue? > > thanks There are two things at play there - jitter and the quality of the DAC (either external or internal). If you were using the CD player as a digital transport (i.e. sending its digital out into the same DAC as the SB) I think the SB will probably win or tie, as its jitter is supposed to be (and has been measured to be) very low. Of course jitter can't really be quantified with one number (it has a spectrum), but I think the SB jitter is so low it's below the quantization error inherent in 16 bit audio, and hence should be totally inaudible. One caveat is that this applies to jitter measured at the SB digital out, but additional jitter will be induced by the connection to the DAC. Some external DACs (Benchmark for example) claim to be able to eliminate jitter entirely via rebufferring. I'm not sure this is really possible, but if true it would make essentially all digital sources sound exactly the same. On the other hand if you compare the analogue outs of the CD to the SB with or without external DAC, there are now more variables in play - the relative quality of the DACs, etc. Furthermore some high-end CD players have fancy systems for reducing jitter in the internal connections (for example using the same clock for both the buffer output and the DAC). In any case I suspect the most important factor here is the quality of the analogue output stage of the DAC, rather than jitter. As an aside, I think the differences involved here are far, far less important than those due to speakers and room acoustics. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=24670 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
