Re: [SlimDevices: Audiophiles] SB2 and PS Audio Digital Link DL III DAC or Transporter?
C_W;437377 Wrote: > Originally Posted by occam > IMO, you'd be far better off with the Transporter, as I think the PS DL > III a very mediocre dac. Strident, unresolving YMMV > > I own both the PS Audio DLIII(unmodded with an SB3) and a Transporter. > I am very happy with the DLIII and wouldn't hesitate to recommend it. I > don't find it "strident" at all. I've never taken the time to do direct > controlled comparisions with it vs the transporter. I have it in my > bedroom running through a Linn Classic to Zu Druids and it sounds great. As I said, YMMV (your mileage may vary) I've not heard the Cullen modified version. I compared it to my modified Zhaolu 2.0 (internal ac power filtering, jumpered out electrolytics between CS4398 dac and analog stages, BB OPA2107 opamps for filtering, and NS LM4562 output opamp, simple opamp swaps) using a Stereovox digital cable. Both dacs were continuously powered for a couple of hours before and durring listening and each was isolated from the AC mains via additional isolating power filters. The Zhaolu cost $275 before my diy mods. The DLII owner, myself, and a few others did the listening comparisons. My previous characterization was charitable, to say the least. This is not to say that the DLIII isn't an ideal complement to your system, simply that it impressed noone when slotted into mine. Its owner has since traded 'down' to a Beresford dac(dunno which one, and I've not heard it)and couldn't be happier. YMMV FWIW, Paul -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=65035 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] SB2 and PS Audio Digital Link DL III DAC or Transporter?
IMO, you'd be far better off with the Transporter, as I think the PS DL III a very mediocre dac. Strident, unresolving YMMV -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=65035 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Audiophile power supply / conditioning
sxr71;401173 Wrote: > Yeah but people buy $5000 power cables and useless crap like that which > couldn't make 5% of the difference of regenerated power. I saw an > online UPS for $399. I'll bet anything it will make more of a > difference than any snake-oil impregnated power cable you can find. Would you provide a link to that $399 online UPS? Thanks in advance, Paul -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=52348 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] linear power supply for duet?
slimkid;329335 Wrote: > So, with all that experience that you have, it didn't cross your mind to > use two duets, one with switching and another one with linear supply and > stick them into the same preamp. > > I'm not an expert at all in any of this, but if somebody tried to sell > me something that doubles the price of the original product, I'd expect > them to somehow show me that it works. DBT might not be worth it to you > - quite contrary, but to me, as a paying consumer, it certainly is. > > K Indeed it did. And if I were comparing 2 linear supplies, I'd do exactly that, get the results, and conduct the same tests again with each supply powering the other Duet, to confirm if differences weren't due to variations between the Duets. But it has been suggested (I believe even by SD personel) that although the output of their switching supply might be perfect, switching supplies do put noise onto the AC line itself to a greater or lesser degree and other, [less well] designed components can be succeptable to that noise. I've concluded the SB supply can be improved both as to the specific performance of the SB/Duet and also how it impacts other components. One can minimize the later with individual powerconding on everything else, save the SB/Duet supplies. I've done this on both the SB, NuForce amps, and other units with switching supplies, these low current draw components should all be isolated from other components. But that still leaves it quite difficult to perform a valid when comparing a switching and a linear supply when both units must be powered simultaneously. Maybe you could only power the 'under test' supply and only during a very short transition/muted time have both on, i.e. a 'make before break' powering of the supplies. But then (justifiably?) someone would argue the the supplies take far longer time to stabilize into their proper stabilized performance. Maybe you are right, a commercial vendor should have to 'prove' the efficacy of their wares. I just don't believe its as trivial as you think. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=51079 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] linear power supply for duet?
slimkid;329282 Wrote: > Make an offer to him - double or nothing. If he catches it on DBT, > double the price, otherwise, get it for free. He shouldn't have a > problem accepting a deal, after all an improvement is noticeable. > > K Perhaps you could share your expertise on exactly how one would go about doing a DBT, or a SBT or ABx for that matter, test on a powersupply for a SB/Duet? Due to the transitory nature of aural memory, for a valid test, one would need to switch the supplies within about 3 seconds, without turning the SB/Duet off. Its quite interesting that inevitably the shibboleth of DBT is allways invoked by folks who've never actually done a valid one, or an invalid one for that matter. No, I haven't done a DBT test in over 30 yrs; its frankly not worth it to me, to switch via a computer controlled relay driven by a recording pseudo random binary generator, even if were possible to do so. But I do valid SBT and ABx all the time in developing my power condioners, because you can bypass them and then take them out of the circuit completely via switches without dropping power. Its an very useful tool. I've no issues with properly implemented blind testing. It would be nice if other posters had actually done any (I might well have missed them) and shared their experiences, rather than reflexively invoking that tired shibboleth. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=51079 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] digital is digital OR NOT
DCtoDaylight;324918 Wrote: > I'm afraid you don't understand what jitter is... > Jitter is variation on the timing of one sample to the next. You can't > remap jitter, it has no effect on the data (unless it's so grossly large > that it causes read errors, not the case here). > > Most sample rate conversions, particularly ones that move from 44.1k to > 48/96/192k are fully asynchronous. As a result, they totally remove > incoming jitter, because the incoming clock is not used at all in > clocking the output data. If the DAC1 does this sort of SRC, and > doesn't block incoming jitter, then someone messed when designing it. > > > Dave But with asychcronous reclocking you certainly embed it from the analog domain of jitter within the digital signal. Simply consider a asychronous reclocking from nominal 44.1kHz to the same 44.1kHz. Unless both the input clock and reclocking are jitter free as well as exactly the same frequency, the result is not going to be bit perfect, nor is it going to be and exact shift of a perfectly interpolated signal. As to whether this distortion is discernable, dunno, but that is not answerable by hand waving in other words, what Patrick said above. FWIW -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=50147 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Transporter Troubles
Indeed, if we could just keep that pesky AC from our power transformer's primary, then the 'bonus' DC would be no problem at all. Your 'subtlety' is not lost at all; it conveys a great deal... -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=30856 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Transporter Troubles
opaqueice;219325 Wrote: > There's no way DC can make a transformer (or anything else) hum. http://www.ewh.ieee.org/r6/san_francisco/pes/pes_pdf/PGE_Presentation_TransformerHum.pdf The Creek amps were/are well known for their toroid transformers humming with the presence of an dc on mains lines (easily seen with a dual trace scope with both ac and dc coupling), and the elimination of such demonstably eliminates that hum - http://www.diyaudio.com/forums/showthread.php?threadid=104626&perpage=25&pagenumber=1 -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=30856 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Transporter listening test
Johann - It was. The difficultly of the internet is that we often misinterpret other's posts, at least I occasionally do so. Regardless of the fact that Ted is evil, occasionally misinterprets posts, he still has good taste in audio components. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=35068 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Transporter listening test
johann;218695 Wrote: > How about a simple "I'm sorry"? ;) OK, I'm sorry (on so many levels...) -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=35068 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Transporter listening test
EvilTed;218371 Wrote: > Have you ever heard an InnerSound setup? > > Stereophile class A all the way and the best hybrid electrostatic setup > I've ever heard... Here's my friend's (Innersound's former marketing director) Kaya system with the panels driven by the never released Innersound Itube 150wpc tube amp. The Kaya's (and your's) crossover/bass amp provides stunning bass authority and clarity. Its among the very best systems I've ever heard. He is primarily a vinyl guy; the Redpoint has been upgraded since the picture. The pre is a CAT, +---+ |Filename: innersound.jpg | |Download: http://forums.slimdevices.com/attachment.php?attachmentid=3104| +-------+ -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=35068 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Transporter listening test
Ted - Evil you may be, but good taste in audio components -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=35068 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Upgrading the Power Supply
Darren, Sorry, the Krell threw me off, and I assumed you were Stateside. From the enlarged picture of your conditioner, its using a common mode choke, as does mine, but beyond that, I can't definatively comment. Its choke is a smaller size physically than I use, but I don't know its core composition, or inductance value. As you're on 220-240vac mains, your current consumption is half of what it would be in North America, and its not as large a concern. From the specifications, its decreasing attenueation of normal mode noise is expected due to frequency dependant permability and interwinding capacitance, same as I get from my own conditioners. The symmetry of the windings are not as precise as the CMCs from Miller or Wurth, but given its cost, its appears to be quite nice. You'd be hard pressed to build one with the same capabilities for the same price from scratch. I'd be curious as to your differing subjective evaluation (if any) with various components plugged into the conditioner vs. that when plugged directly into the wall on the same circuit. Regards, Paul -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=20855 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Upgrading the Power Supply
Darren, If you're willing to form your own conclusions, you might consider putting your source components on an inexpensive diy powerconditioner. http://www.diyaudio.com/forums/showthread.php?postid=1241102#post1241102 Given the low power draw of your source components, you could even consider using a higher inductance, lower current capability CMC, the JW Miller 8110-RC which is offered at promotional pricing, in addition to those mentioned in the referenced thread. FWIW -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=20855 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] bybee discussion on ac
Gents, I'm quite flattered that my moderation merits your discussion. Some points of fact - 1. I'm simply going to SPLIT the thread into 2 separate threads on the same Lab Circle. No posts will be lost or censored. The original thread will contain results and discussion of actual measurements. The persons who actually made the efforts of empirical measurements want this because they (and I) would like folks to be able to access actual information and discuss the meanings of those measurements, without having to sift through 17+ pages of twaddle and accusations. 2. Discussions OF actual empirical DBT, SBT, ABx tests are encouraged on the AC Lab Circle as long as they are presented by the person who actually performed the test. Indeed, this is censorship; I view it as an effort to maintain a high SN ratio. I see no point in endlessly rehashing the same material ABOUT testing. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=34154 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Q: Inexpensive Linear power supply
creativepart;190740 Wrote: > Sure wish this post was about "Inexpensive Linear Power Supplies" as the > title suggests. > > Now that would be worth reading. http://www.herbach.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=HAR&Product_Code=TM01PWS4465&Category_Code=PWS Described incorrectly as a - 5 VDC @ 1.5 Amp. Input 115/120 VAC,60Hz Switching Power Supply and in reality it is a linear suppy. It will require replacement of the DC connector. $5.95 The above is actually the same as this Hosfelt supply, which also requires replacement of its (different) DC connector. Go to - http://www.hosfelt.com/ click on 'adapters' on the left hand menu click on 'regulated' Its the first entry - 5 VDC @ 1.5 AMP Regulated Power Supply $6.95 A goodly number of these supplies will exhibit hum, to varying degrees, as typical of EI core transformer supplies. Its a crap shoot. This supply will have less propensity to hum, but you'd need to put it in an enclosure, provide cords, etc... http://www.herbach.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=HAR&Product_Code=TM96PWS2913&Category_Code=PWS -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=33547 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Q: Inexpensive Linear power supply
opaqueice;190717 Wrote: > We're not talking about scientifically acceptable results here - just a > minimal, good-faith attempt to verify there really is an audible > difference. As some people never tire of pointing out, a negative > result on such a test doesn't prove it isn't audible - but a single > positive result provides pretty compelling evidence it is (although of > course it doesn't prove anything either). So the deck is really > stacked in favor of someone that claims there might be a difference. > > You're complaining audio memory is short, so the difference might get > lost due to too-long switching times. Just think for a moment about > that. A volume difference of 1 dB, and probably a lot less, is easily > identifiable in these tests. Something which isn't is therefore more > subtle that a slight change in volume. It's so subtle you can't keep > it in your mind long enough to tell the difference after a few seconds. > At that point, do we (as audiophiles) really care? If the answer is > yes, we'll have to work harder to make DBTs which are capable of > overcoming that (and they exist, for example computer-based tests). > But for me if I can't hear the difference after a second or so spent > switching something, I'll find better things (like speakers and room > treatments) to spend my time and money on. > > > > That's your perogative as moderator, but personally I don't think > censorship is ever a good idea (and that applies equally to the > hydrogenaudio forum policy). I'm glad there is no such policy here, > and I don't find it worthwhile to read or post much on either of those > fora because of those policies. opaqueice, Please note the section of my post that you didn't reprise occam;190702 Wrote: > . > Its straightforward to set up valid SBT or ABx tests, iff you have > circuit level access, and you're dealing with a situation where > (generally) nothing is turned off, levels matched and interruptions of > sound <5 seconds. This is why the Good Lord, in Her infinite wisdom, > has given us 4pdt switches, if you're dealing with something as > straightforward as power conditioning. And its not that incrementally > difficult to extend those tests to DBT with a computer and sufficient > quality relays. But other areas good luck I'm well aware of the issues of subjective preference for the louder, all things being equal, or even not so equal. But luckily for me, my diy interests are in the realm of power conditoning/supplies. And in that specific situation, volume issues are reasonably moot. My effectively Bailey topology power amplifier is basically a big opamp. Same for most preamps. And both linear and switching supplies are generally controlled by opamps, so unless there is something radically unstable in the voltage references of those supplies, those issues are not issues with reasonable care. Assuming adequate voltage rails, gain is determined by the feedback resistors. A compentently implemented resistive attenuator or the digital attenuation capability of the SB, make volume differences (at least at the output of the amplifier) a non issue. As far as testing amps, preamps, cables, etc good luck with that. And if you're willing to surgically get at the wires of a ps and/or conditioner, switching for ABx, SBT, and/or DBT is quite easy. I don't buy anyone's supplies or conditioners, I build them. Iff'n you think the $20 it takes to build are really excellent power conditioner is money better spent elsewhere, thats your call. If you think the mains power in the Nu Yawk is adequately addressed by the switching carbuncle provided with the SB, you're a lucky fellow. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=33547 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Q: Inexpensive Linear power supply
opaqueice;190587 Wrote: > I agree with most of what you said here, but I think it's going too far > to say that the objectivists here believe that most tweaks are a waste > - personally I believe that many of them are, but certainly not all, > and I don't know about most. What's frustrating is how easy it is to > check whether a given tweak actually works, and yet how totally > resistant the proponents typically are to doing so. Given the brevity of aural memeory, (borrowing the phrase from Sean) I'll bet dollars to donuts, that few of you have conducted a valid hardware DBT audio test. 30+ yrs ago, I did nothing but set up the switching mechanisms for (admittedly non audio) tests at Hopkins Medical School and the Maryland Psychiatric Research Center. Whatever anecdotal results have been discussed here wouldn't pass peer journal review criteria of those days, let alone whatever minimal criteria are acceptable today. Its straightforward to set up valid SBT or ABx tests, iff you have circuit level access, and you're dealing with a situation where (generally) nothing is turned off, levels matched and interruptions of sound <5 seconds. This is why the Good Lord, in Her infinite wisdom, has given us 4pdt switches, if you're dealing with something as straightforward as power conditioning. And its not that incrementally difficult to extend those tests to DBT with a computer and sufficient quality relays. But other areas good luck. Leastwise, this is what my students, 1 month away from recieving their BSEEs are finding out in their senior lab course. Its actually more comical to watch them breadboard and solder a simple circuit. > I just hope we don't get to the point of censorship, like banning any > mention of DBT (audiocircle) or not allowing any report of an > improvement without having first done a careful DBT (hydrogenaudio). > That really does stifle discussion, to the point that the board becomes > pretty boring. I've banned discussions about DBT in the Lab Circle at AudioCirle, not discussion of actual DBT tests. I'm a strong believer in valid testing. Its appears that folks find it far prefferable to invoke the shibboleth of DBT rather than actually perform a valid one. Personally, I find such discussions 'about' a boring, repetitive, fruitless exercise in Onnanism. But if talking about it, rather than actually doing a valid experiment, floats your boat, enjoy. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=33547 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] MhdtLab DAC
dlite;186583 Wrote: > Personally I think just about any tube adds distortion to the signal not > musicality. Good music should not need to be smeared by a tube to sound > good. Just my opinion. And what makes you think that 'smearing' (lack of resolution?) originates with the cathode follower tube stage? Those who've swaped the extant OPA2604 opamp for an OPA2107 in their Paradisea report a substantial increase in percieved resolution and extention, along with a reduction of 'grit'. I'm not arguing that this change would result in an objectively measureable change, simply a percieved one. But then again, my enjoyment of music is derived from my perceptions. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=33429 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] time for a DBT-free zone??
Does anyone have any references (academic peer review journal quality) on the 'persistance' of aural memory? How long a gap between listening to 'A' and then 'B' can elapse and still have that comparison remain valid? Obviously, this might depend on the magnitude of those differences, but I've found myself in the situation where in doing comparisons, I frankly don't remember with any confidence what the previous sample sounded like. TIA, Paul -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=32352 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] plug and play linear supply (part 2)
GaryB;179017 Wrote: > All of my dearly held world assumptions are crumbling. > > Totoro is lecturing people on civility??? > > Occam is being held up as a model of temperate response and Philnyc is > now the impolite one? > > Next thing you'll tell me is that the Pope isn't Polish. > > ---Gary Gary - I'd like to thank you for that capstone to a truly wonderful day.(my son just recieved fully funded admission to both the Berkley and Chicago grad schools in math) Your post had me laughing so hard I actually fell off my chair. Phil - Give me a call and we can discuss your social skills totoro - re: Your eponymous use of my 'nome de screen', specifically - 'To pull an occam, I think some people need to read the Harry Frankfurter book "On Bullshit".' While my posting style often lacks Phil's usual civility, noone who IMO, communication with results in anything positive for anyone, has ever described them as 'bullshit'. If thats the best you can come up with, I'll not respond to your posts, and would ask for reciprocity on your part. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=32231 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] plug and play linear supply (part 2)
Opaqueice, Dunno, your components have enough resolution that I'd think you should be able to hear a difference if there was one. Beats the heck outta me, as I've heard similar improvements with upgraded power supplies, as others have. Regards, Paul -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=32231 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] plug and play linear supply (part 2)
Opaqueice, Would you please list/describe what is in the signal and power chain of your system? TIA, Paul -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=32231 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Best reasonably priced DAC
Fkuti, In comparison to my modified Zhaolu 2.0, its far more resolving. No, its not the equal of PhilNY's Dodson, but then again <$400 delivered vs.$8k is a big difference. The Citypulse is, IMO, a better DAC than anything until you start talking big bucks, $2K+ Then again, I've not heard everything out there. The Paradisea is a lovely dac, the tube allows some 'rolling', but frankly, the OPA2604 in it constrains the resolution substantially. Its not nearly as resolving as my Zhaolu 2.0 which allows easily changing the opamps due to their being socketed in the Zhaolu, unlike the Paredisea. I'm awaiting some feedback from some freinds who've I've given a OPA2107 and LM4562 to try in their Paredisea as a replacement. FWIW, Paul -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=32336 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Best reasonably priced DAC
No, not a LC Audio Zapfilter, but like it, a discrete output stage, housed in red translucent boxs. http://www.diykits.com.hk/dac.html a very, very good dac -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=32336 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] plug and play linear supply (part 2)
totoro;178295 Wrote: > There should be a special line in that page for people who make the > following argument: > > I think you are wrong: furthermore, I'm going to make an implicit claim > that you are committing a fallacious argument of known type, as listed > on this page, but I won't tell you which. > > Aside from having no validity as an argument itself, the implicit > "you're dishonest/stupid" component is fairly uncivil. > > So I'll reply in kind: the "argument" you just made can fairly > charitably be called bullshit. And this is entirely independent of > whatever the position you are opposing happens to be. Well golly, I certainly don't understand why you've go your knickers in such a twist. CeeJay was simply relaying a comment from someone at Slim Devices, caveated it as such, and asked for comments. Given the care with which he posted, I've have no issues with his post. The point I was trying to make is that in both science and engineering, a plausable and logical hypothosis is a far cry from a compelling and definitive proof, especially when it never goes to the next step of empirical verification. And yes, this is covered in the referenced url, as is 'changing the subject', 'moving the goalposts', 'ad hominem', 'appeal to authority', etc... which is applicable to many of the posts on this board, including my own. I think that url is a wonderful reference - http://www.don-lindsay-archive.org/skeptic/arguments.html as I often read posts, including my own, and have trouble giving name to the particular error in logic/rhetoric. If you feel the reference is of no use to you, ignore it. As to the actual subject matter at hand - I have the little Unifive +5v wall wart in front of me. Actually, it also makes an equal caliber -5v supply with a switching of the connector, as it is a floating supply. Its noise production is both transverse and common. That common mode component is exacerbated by the long, parallel, non shielded leads. Similarly, 6'+ of 21ga?? ground lead is less than ideal. Nor is there, I assume, given its less than 2 cubic inch volume, much room for the inductive components generally found within far larger and more expensive switchers to deal with noise. And ultimately, that ground is referenced to the signal ground on both the RCA analog and digital outputs, which by a circuitous path ultimately establish a ground reference. All I can suggest is that folks might read Bill Whitlock's (at the Jensen transformer site) papers on 'dirty grounds'. FWIW -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=32231 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] plug and play linear supply (part 2)
peejay;178173 Wrote: > Let someone shoot me down here, but according to a brief e-conversation > I had with someone from SD, because the 5 volt regulated supply into > the SB is up-converted to various other internal supply rails and these > then regulated internally *again*, it is these internal rails which will > more likely affect the quality of the audio, so there's meagre pickings > which are to be gained by messing with the original supply. But, due to > the intense emotional and fiscal investment people on this forum have > already made on this topic, I'll bow out now and let the flame wars > begin..:-) > P.S. This didn't stop me from making my own battery-powered supply just > in case ;-) Perhaps the well reasoned and plausable conclusion from this non-empirical thought experinment is not entirely correct.. I find the following link particulary interesting as an adjunct when reading this forum - http://www.don-lindsay-archive.org/skeptic/arguments.html -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=32231 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: The modifying crowd and the Transporter
seanadams;142919 Wrote: > > Of course, I listen all the time. There are many things that are easy > to hear but hard to measure, particularly with respect to the codec > algorithms. However, I don't design the products to satisfy my own > subjective preferences. When it comes to the DAC, things like the noise > floor and harmonic distortion are simple measurable quantities that can > be minimized through careful design. Sean - Thank you for the well reasoned explanation of you design goals. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=28080 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Transporter, Inside Out
Sean, Thanks for the reply. Given your choice of dac and ouput chips - 1. Is each output phase/channel produced by a single 5534 recieving both phases of that channel from the dac. The other output phase is produced by the same but with the output phases of the dac chip reversed for input into the other opamp? 2. Given the bipolar input opamps, the outputs from the opamps are cap coupled? 3. Are to ouputs from the dac (inputs to the opamps) cap coupled or do they rely on common mode offset rejection? TIA, Paul -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=27927 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Transporter, Inside Out
Sean, Are you making use of the compensation pins on the 5534s, and if so howso? TIA, Paul -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=27927 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Squeezebox Class D!
Softwire, While the Panny's sound isn't my cuppa, that is subjective. Given your components, I'd say you're done and should enjoy it and not obscess over further upgrades, as you'd be climbing a very steep cost vs. benefit slope. Kudos, Paul PS - Apologies to the forum participants for the OT diversion. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=27452 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Squeezebox Class D!
Softwire, The only thing I ever polish is my shoes, and that very rarely. As to your using your SB as a transport (you didn't mention your DAC), I'd suggest you first try a good glass toslink - http://uniqueproductsonline.com/gltodiopca.html and yes, I've heard all the badmouthing of toslink, but these are not the toslinks of yore. Unless your SB2/3 to DAC spdif link is galvanically isolated with a transformer at at least one end, IMO, you're better off with a good inexpensive glass toslink. Beyond that, I suggest really good power conditioning for your SB and DAC. FWIW, Paul -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=27452 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Squeezebox Class D!
Phil Leigh;137503 Wrote: > I'm hardly anonymous! Get off my case. > > As I wasn't there (obviously) I can hardly comment (and wasn't) on what > they heard - although the amount of empty bottles is slightly > worrying...). Well golly, at least our drunken stupor had some consistently. We also found that a modded external DAC, $200 all in, including swaps of the 3 socketed opamps, although impressive, didn't equal the $8,000 Dodson. Same thing as the SB, save for the fact that those who brought the DAC, agreed, didn't whinge about it and make snarky comments > Why didn't they post on this forum? Given the faith based opinions expressed by many here, I'd assume folks didn't want to put up with the inevitable whinging. Is it devatating news that a given product 5x+ more expensive might be better? Nor does concluding that the SB isn't the bestest transport in the whole wide world take anything away from the tremendous value that the SB3 offers. > Everyone is entitled to their own opinion. Mine is that the SB can (in > the right setup) equal or better ANY spinning disc transport. Indeed, opinions are like bodily orifices, everybody has at least six. I might even judge yours to be credible if it was based upon comparisons to an Oracle of Aberdeen modded Nothstar. That being said, I do feel the SB2/3 is the best transport one can get for <$500 ($300 for the SB and $200 to diy a proper ps and powerconditioner). That SB is certainly better (IMO, based on actual comparisons) as a transport than an EA modded Sony S7700, which in olden days was quite highly regarded. > YMMV now back off. Back off from what? You, or just my responding to the (IMO) silly comments you make? -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=27452 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Squeezebox Class D!
Phil Leigh;137450 Wrote: > Well, I don't want to be accused of cynicism (again) but the phrase > "they would, woudn't they" springs to mind... Don't worry Mr. Leigh, I don't think anyone who'd actually read what was said - http://www.audiocircle.com/circles/index.php?topic=29391.90 would think your comments motivated by cynicism; altough the expression 'gutless innuendo, encouraged by the anonymity to the internet' might spring to mind. You owe PhilNYC, (and all the participants of the AC NYRave) an apology for your baseless comment. At that same Rave, the stock Olive Opus was thoroughly trashed. Why are your knickers in a twist that everyone agreed that a $4000+ Oracle transport outperfomed a SB(even with upgraded PSs)? -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=27452 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Preamp Volume Control - how does it work?
Andy - Thanks for the clarification. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=26788 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Preamp Volume Control - how does it work?
http://forums.slimdevices.com/showpost.php?p=33384&postcount=3 per Sean Adams - Sean Adams;33384 Wrote: > Right now we are doing the volume in the CPU, for both s/pdif and DAC > outputs. The DAC also has volume control capability but we're not using > it at the moment... -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=26788 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Transporter design question
Sean, Are the switchers within the Transporter connected to the mains, as the suppied wall connected supplies on the SB2/3 or powered off a dc rail like the internal switchers in the SB2/3? Thanks in advance, Paul -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=25919 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Slim Devices Transporter?
I think the implementation of transformer coupled BNC and cap coupled RCA SPDIF is an excellent approach that addresses both the needs and the dross of the audio community quite well. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=25773 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SqueezePower final design Power supply
Hi Patrick, Are you the clever fella who bought all the remaining Power-One supplies from CascadeSurplus? -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=23227 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Need help on OPAMP and output Cap replacment
Yes, the OPA2604 comes in the same so8 footprint as the existing opamp. There are no sockets available, to my knowledge, for so8. Nor would I think it feasable to put in a dip8 socket in the SB to allow easy changes, as I don't think this adapter would fit due to vertical space limitations - http://cimarrontechnology.com/index.asp?PageAction=VIEWPROD&ProdID=20 But you really should make an effort to answer at least a few of these questions for yourself. A simple google seach on 'opa2604' would have trivially given the answer to 'does it come in so8 smt format?' The opa2604 is a reasonable choice, not particularly bad, not particularly good. Subjectively, IMO, its just OK. As the opamps are bracketed by caps and you're running single rail, there is no compelling reason to use such a Fet input dual opamp, unless you particularly like the subjective sound. Bipolars (like the one that is presently in there) will work well. I've a number of preferences that would work well in this environment, So8 duals in both fet and bipolar input, but as I've not set up those proper double blind experiments, I dare not opine. When a diy forum is set up here, maybe some of the diy expert engineers with over 30yrs of expertise will advise you, and help you set up those proper controled experiments to evaluate whatever changes. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=22748 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Hosfelt PS - I AM LOSING MY MIND, HELP!
Is your multimeter still working? Measure a 9v battery (make sure the battery is working by holding it to your tounge) or a cell phone battery whatever. Is the outlet you're plugging them into still working? Plugh a working lamp into the outlet, etc or you might possibly loosing your mind. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=23093 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: DIY Forum?
A poll associated with this post was created, to vote and see the results, please visit http://forums.slimdevices.com/showthread.php?t=22944 Question: Should there be a DIY Forum? - Yes - No - Need to think about it some more Dean, Many thanks. Just remember, no good deed goes unpunished. Regards, Paul -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=22944 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: DIY Forum?
A poll associated with this post was created, to vote and see the results, please visit http://forums.slimdevices.com/showthread.php?t=22944 Question: Should there be a DIY Forum? - Yes - No - Need to think about it some more Ezkcdude, Dunno I rather like the involvement of 'for profit' modders even in a strictly Diy environment. Modders such as VinnieR and Wayne have been quite helpful and generous in their comments and suggestions on a Lab board where I'm the moderator. And I even found the over the top, hyperbole used to describe those Maui mods quite useful. It confirmed, somewhat, my choice of the LT1764 regulator, and I'll investigate those specific Sanyo caps. I'm not that proud and will take advise where I can get it. At least they have actual specific empirical experience. Its only when a vendor says 'this is beyond you' does it behoove the moderator to firmly say - "Hey bud, you don't come into MY house and piss on my shoes, and I won't go into your house and". Even though they might actually be right. Nor does it serve any purpose to criticize those 'obscene profits' of those vendors. We all expect a living wage, but we seem to begrudge the same to others who wish to derrive a living wage from their efforts. If we don't like it, all we've got to do is show how we can achieve the equivalent for far lower cost (and always remembering that our time has absolutely no value whatsoever). No one is forcing us to purchase their products. And frankly, it was those armchair objectivist 'engineers' that provoked that vendor to (over)react in defense of his 'pride and joy'. While I'm personally a believer in DBT, I simply don't allow discussion of DBT (or 5 string banjos) in my Circle. No good ever comes of it. Nor do I know of any useful board that allows it. FWIW, my experience is that any DIY board requires strong (when needed) moderators, specifically because egos are are so intrinsically involved. It also reqires specific defined posting rules lest chaos ensue. Sadly, moderating a DIY board takes entirely too much time and effort. Any volunteers? Regards, Paul -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=22944 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: DIY Forum?
A poll associated with this post was created, to vote and see the results, please visit http://forums.slimdevices.com/showthread.php?t=22944 Question: Should there be a DIY Forum? - Yes - No - Need to think about it some more Prior to today, I would have thought a DIY forum was an excellent idea. But Kevin Pearsall's, Customer Support Manager, action of today makes me think it a foolish and wasteful idea. Kevin has seen fit to delete the entire thread 'Power supply upgrade'. This WAS a Diy thread. And yes, it recently devolved into a 'flame war'. I've no problem with the administrators of this site deleting those posts which are offensive. But to delete the whole thread is to tell those posters that did not 'flame' and put considerable effort and time into their own 'by the rules' posts, is to tell them that their efforts are worthless. Flame wars are inevitable in DIY audio (the discussions are so heated because when you get down to it, so little is really at stake). Personally, I'll confine my discussion of DIY efforts to boards where the moderators are no so ham handed. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=22944 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Power supply upgrade
Regardless of your mains powered ps, at least in NYC and the Washington metropolitan area (the homes of all things corrupt, including AC power), you'll probably benefit substatially from good powerconditioning fronting your power supply. http://www.audiocircle.com/circles/viewtopic.php?t=26627&start=0 FWIW -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=20844 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Q on the internal SB2/3 switcher
Andy, Sorry, my title for the thread was very ambiguous. Thanks much for the info on the stepdown switcher used for the digital circuitry. >From a previous post by Sean (specific to the SB2)- Code: AC -> 5V 2A -> Dual > 3v3 (IO, wireless, logic) SMPS| Switcher > 1v2 (CPU core) | |> Linear reg > 3v3 (headphone) | | |> Switcher > Multiplier -> 11VAC VFD ef || || 14VDC ||---> 55VDC VFD vdd2 --RC filter<-| | | |--> Linear reg ---> 9vdc (op-amps) | |--> Linear reg ---> 5vdc (DAC) What I was actually inquiring about was the 'switcher' that feed the multiplier (Cockcroft-Walton) which generates the 11vac and 55vdc (for the display?) and the 14vdc which is decoupled by that bigass(tm) cap and ultimately the linear regulators feeding the dac and opamp. My question was how is that specific 'switcher' implemented, i.e. a multivibrator? and at what frequency and duty cycle? Sean - Would you please enlighten? Thanks, Paul -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=20884 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Power supply upgrade
Funkmaster - Its probably a switching supply, not a linear supply preferred by many. The '100-250vac' is indicative of a switching supply. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=20844 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Modifying the Squeezebox 3
Dorkus, I do believe we are talking at cross purposes here. Please read specifically what Mamsterla posted - mamsterla Wrote: > Gary: > I forgot to mention that my SB2 is modded with a linear, LT1086ADJ > regulated PS and has a new Rubycon ZA "big ass" cap with a 0.01uF > Siemens stacked polyester bypass cap on it. He nor I made any mention of ps decoupling of digital circuitry, only a reference to his rather well chosen (IMO) analog ps. Neither he nor I advocated replacing a smt ceramic for digital decoupling with a stacked film leaded cap. Why in heaven's name would you think we'd done so? Now when I read Mamsterla's original post I made some assumptions - He chose the LT1086adj, even though LT1086-5 s are available specifically because he could capacitively bypass the ground leg of the voltage set resistive divider for better performance than the non-adjustable implementation. He implemented his ps on some perf board or 'dead bug' and using smt components is simply not practical. And his use of those Epcos stacked film caps is very astute in the context of a non-smt based implementation. Similarly, while I do like the Panny FM electrolytics, as they're readily available, from objective criteria, I can't see why they'd be prefferable to Rubycon ZAs. This implementation potentially offers far superior performance than than the ULN723 based regulated supplies that folks hereabouts are so excited about (and as the original source for the recommendations on AudioCircles of the Hosfelt and the PowerOne supplies from CascadeSurplus, I feel entitled to make such assertions, and only suggested them as a quick and dirty cheap altenative and not as the equal of a well implemented ps as done by Mamsterla) and more importantly, is relatively straightforward to do so. I'm eagerly awaiting your offer of a smt based external linear supply, with double sided boards, proper ground planes for lowest noise, and provision for the 'proper' components. But until that time, I'd think the proper response to Mamsterla would be to ask for advice. FWIW, Occam PS - Thanks for the nerdy references, but save for that 1st general reference, it might be beneficial to make them relevant to the subject at hand, decoupling of LINEAR (PS)circuits. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=19822 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Modifying the Squeezebox 3
dorkus Wrote: > you may want to try w/o that polyester film cap in there too. film caps > actually aren't very good for supply bypassing in high-speed (e.g. > digital) circuits. the parasitic inductance is much higher than > eletrolytic or chip ceramic caps and can screw up the sound. YMMV, but > some people feel they add coloration... You're kidding, right? The Siemens (now Epcos) stacked poly caps are known for their very low inductance, and are specifically used in ps bypass of high speed circuity. As to an objective/subjective preference for polypropolene over polyester, that may be but Epcos also makes these stacked architechture caps in polypropolene, though more limited values, the .01 being among them. The nekk'd stacked polyester from Epcos, available from Maplin in the UK, are legendary for that application. Go to digikey, and download the PDFs, and then tell us as to their applicability. The encapsulated Epcos polyesters are series B3252xxx and the polypropolenes ar B3262xxx. FWIW -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=19822 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Q on the internal SB2/3 switcher
Sean, You've previously described the ps for the display and susequent analog regulators as a switcher with a Cockcroft-Walton voltage multiplier. The voltage multiplier is relatively straightforward, a bunch of diodes and caps in that classic topology.[folks unfamiliar can simply do a Google seach on 'Cocroft-Walton voltage multiplier'.] Would you describe the switcher part in a bit more detail, specifically the implemetation (555 multivibrator or suchlike?)frequency and duty cycle. Folks seem to think that because you've descibed it as a switcher that it is inherenctly spewing artefacts and is a limiting factor. Given the elegance and expertise which defines the rest of your circuitry, I'd assume your implementation is far more benign. Thanks in advance, Occam -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=20884 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Reality Check: Power Supplies
tyler_durden Wrote: > I think a lot of people have missed the fact (revealed in other threads > by the CTO of slimdevices) that the power for the analog stages in the > squeezebox comes from the HV switching converter on the display board. > > > You can mess around with linear regulated supplies and ferrite beads > external to the squeezebox all you want but that won't change the fact > that the internal supply is a switcher. The switcher drives linear > regulators that supply the audio circuits. > > If you open the thing up and replace the switching supply for the > display with a linear regulated supply you might be doing something > meaningful (or you might not). > > TD Huh? There are switching supplies, and then there are switching supplies. Indeed, Mr. Adams charaterized that supply as switching, but one could assume its a multivibrator? (a 555 or suchlike), feeding a voltage multiplier (a bunch of diodes and caps), and as to whether its spewing noise would depend on the implementation. Its the same topology that was used in the DI/O which certainly was not problematic, or noisy, by any means. This is hardly the same as those little wall carbuncles. Perhaps Sean could be a bit more specific as to the switching methodology and frequency (the voltage multiplier is already known to be a Cockcroft-Walton multiplier). Tyler - it serves no one to paint with such a broad brush without sufficient background information. Regards, Occam -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=20725 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Modifying the Squeezebox 3
Skunk Wrote: > Sean posted one. I'm afraid you'll have to search. I did to no avail > (didn't see it linked from www.seanadams.com either) http://www.seanadams.com/dac.pdf -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=19822 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Anyone here got a $50 power cord?
ezkcdude Wrote: > So, how are these blind tests done? Do you do at least 16 ABX trials? > That's about the minimum that can give statistically signficant > results. > > Also, as far as there being a difference between cheap power cords and > the fancy ones, don't you think manufacturers of $10,000 amplifiers > supply decent power cords? It seems a little crazy to me that the same > amplifier, as well as other component, manufacturers would go to such > great lengths to engineer high end products, and then hamper them with > AC cords that don't work properly. But hey, who needs logic when you > have such "golden" ears. Frankly (ezkc)dude, I could care less what you do or do not believe. Nor do I care or see the relevence of yet another of your 'thought experiments'. My comments were specifically about the differences between 2 $6 powercords, not about $10,000 amplifiers, or the marketing decisions of their vendors. Your CDD (comprehension deficit disorder) is not my problem. Please make an effort to stay on point. But I do largely agree with Phil that some of these expensive powercords have tremendously beneficial subjective effect. I'm simply too cheap to spend the monies, and stick with my specific $6 cords, preferring to spend my efforts on building my balancing powerconditioners (yeah, I know, if the sound if effected the powersupply designer failed, quack, quack quack). Indeed, I'll try to make it over to Phil's. I'll also bring over a surplus discrete 5v powersupply for his SqueezeBox as well as my Felicia conditioner, and if it provides a benefit over the Hosfelt and PowerOne from CascadeSurplus powersupplies(I was the original source for those reccomendations) I'll post about that. Ezckdude - Have you actually done anything to your SqueezedBox? Or do you simply post your thought experiments and their conclucsions?, alleviating yourself of the necessity of empirically doing anything? -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=19818 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Anyone here got a $50 power cord?
PhilNYC Wrote: > ...If there's anyone on this forum in the NY/Northern-NJ area who is > interested in doing a blind test, I'm willing to host a session... Now Phil, why would anyone have to go through the effort of empirical verification when thought experiments are so convincing? Obviously, we all think our own thought experiments are totally vialid, whereas its those other folks (everyone else's) whose efforts are so flawed. I'd even agree that sighted comparisons can be invalid, with that Hawthorne effect and all. But I and others have done their own blind experiments between two cords, Volex and Unicable, both shielded 14ga, with molded terminations and <$6ea, on a 100 watt poweramp to convince ourselves that such differences do exist and are repeatably identifiable. 4pdt switches are amaizingly useful things. But I really do enjoy these well crafted explanations that always implictly end with 'thus, I refute you.' Sure beats getting off your arse. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=19818 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Modifying the Squeezebox 3
davehg Wrote: > .., he knows the gear, and has modded countless SB2's and SB3's. > Plus, he backs up his work... I know Wayne and respect his work. I think he is far more numerate than you give him credit for. -- occam occam's Profile: http://forums.slimdevices.com/member.php?userid=949 View this thread: http://forums.slimdevices.com/showthread.php?t=19822 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB2: reduce analog out voltage by 10x?
Just a quick comment to say how impressed I am with the speed and sophistication that you've brought to bear in making the variable outputs flexible and resolving. Kudos! -- occam ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB2: reduce analog out voltage by 10x?
Dang Jacob. I was editing that post and I see you copied the edited, more 'tasteful' version of the anecdote. I saw Usual's reply, while editing, mentioning that the Parasound had attenuators on its inputs which seemed to address the problem quite well. So I deleted my post. But you're right, inevitably, you loose resolution as you've only got the 40 set volume levels that are done in software. It would be nice if Sean, et al, would implement 256 levels of .5db attenuation. Barring that, if one doesn't want external attenuators, you could replace the input 4.7k resistors, R37 & R39, of the output opamps, with something close to 11.22k which would bring down the max to about .775Vrms. http://www.seanadams.com/dac.pdf This would still give those 39-40 steps up to the max desired output, which begs the question of whether X fixed steps is ever enough. But I'm old and uncoordinated, and replacing smt resistors is a daunting task for me. -- occam ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB2: reduce analog out voltage by 10x?
A man walks into a doctor's office, and says to the doctor- "Doctor, when I do this with my arm, it really hurts." and proceeds to show his arm all the way up his The Doctor looks at the contorted patient, ponders a moment, and says - "Well, have you considered not shoving up ALL the way?" Have you considered not shoving the volume up all the way? -- occam ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Re-boxing SB2
Andrew L. Weekes Wrote: > I'm not a big fan of batteries, under most real-world loads they are > always worse (noisier, lower bandwidth, poorer transient performance) > than a *well-designed* linear regulator BUT they are possibly easier > for the average DIY'er to get reasonable results from, hence the > appeal, I guess. > > Added to the inconvenience of charging and maintenance, they'll never > be my first choice, I've certainly never acheived state-of-the-art > performance with them. I've never tried NiMH, but have no reason to > suppose their chemistry makes them any better than NiCD for audio. > > Andy. Why in heaven's name, in the context of the SB2, would one compare a raw battery to a linear regulator? Isn't this why the good Lord, in Her infinite wisdom, gave us capacitors? Isn't the proper comparison between a 6v SLA and your toroidal transformer & rectifier bridge? What precludes us from adding those charming Pannasonic FC/FMs or Nichi HE after both? As our basic requirement is a 1 amp, 5Vdc supply, for batteries one presently has to choose a 6v 12a SLA and regulate down. -- occam ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Some Qs on the output configuration
Sean - Which 3.3v regulator is providing the digital V+ for the dac? Is it the supply from the dual switcher, or the 3.3v linear regulator that is also feeding the headphone amp? What is the Part# of the 3.3v linear regulator? Thanks in advance, Paul -- occam ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Tweaked-SB2, some pictures
Michel, Very nice. Why did you choose a toroidal transformer for your external ps? Unless you've used a very expensive interwinding shielded tranny (or an even more expensive Plitron Lo-No), the high bandwidth and capacitive coupling of the toroid is going to let substantial line noise through. To those who say that the ps regulators will deal with that, I can only respond - "piffle, you obviously haven't bothered to empirically verify your assumptions". Try a split bobbin or flathead multibobbin transformer. -- occam ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Some Qs on the output configuration
The output opamp question was with regards to dropping the output gain, basically making it a voltage follower. And yes, I see why you're not using Vcom for biasing as you're not using the 5v as your rail for the opamp. Many thanks. -- occam ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Some Qs on the output configuration
1.The pcm1748 is capable of digital attenuation of -64db in steps of .5db, for a total of 128 settings. The SB2 implements this feature with 40 steps. Is there any practical way of expanding the configuration of the SB2 to access this finer granularity, such as reprogramming EEPROM, if its controlled by such? 2. The output opamp is configured for a gain of about 2. Is it inverting or non inverting? Is that NJM2041 configured as straight amp or as a lowpass filter? If so, how many poles and what is the pole frequency? Is the NJM2041 stable at Av<=1? Can I adjust the gain by changing Ri & Rf? Many, many thanks in advance. -- occam ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Newbie Power Supply Question
Hey Vinnie, Those Acopians are certainly small and well specified. Have you compared their subjective performance to the less expensive and multisourced linear supplies such as those from Power-One, Condor, International Power, etc...? TIA, Paul -- occam ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Newbie Power Supply Question
Sean, Thanks for the quick response. Certainly, scarce resources might be better spent on digital clocking, reconstruction filters, etc... Six months ago I firmly believed powerconditioning, balancing and such were appropriate only for products with poor, inaccessable powersupplies. I've changed my opinion after much empirical work; surely a sign of more free time than common sense. Thanks again, Paul -- occam ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Newbie Power Supply Question
Sean, Its quite refreshing to the CEO being so supportive and open with those seeking to modify his product. So you've gots to get an external powersupply that provides regulated 5vDC and 14vDC. (or that 14vDC could be changed to a charger for a 12v SLA, assuming the dropout voltage of the 2 linear regulators it would feed [to the analog circuitry] allows it. You've got to cut a trace to route your 14vDC in, and void the SB warranty So you need a multibobbin power transformer, not a toroid, bridge(s) [and doubler depending on transformers secondary], ic or discrete regulators and caps As you're using a proper transformer with low capacitve leakage and limited bandwidth, you might as well front that with a single small balancing transformer and appropriate capacitive filtering between, and drop the noise going in, and out. Obviously this hack isn't going to come with UL certification so you need a grounded mains plug, and inevitably we've line noise and grounding issues. I'm a great believer in brute force filtering and symmetrical power for both analog and digital circuitry, as long as you can source inexpensively enough. Which is the sole advantage of the diy community. We can buy surplus crap. Suggestions? What are the 3 pin linear regulators feeding the DAC and opamps? Is the output NJM2041m running single rail with the output electrolytics biased @ +4.5vDC? Many thanks in advance, Paul -- occam ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
