[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: Reality Check: Power Supplies
Skunk Wrote: > Which filtered power stip was it? I know there are some DIY plans out > there, and some audiophile versions that cost more than my last car. Its fairly old now. "Einstein Octupus" or similar.. (eight outlets) I just had it laying around. I would probably spend the money on a different power supply if I didn't have the "Octopus" already. And/or build my own filter. -- P Floding P Floding's Profile: http://forums.slimdevices.com/member.php?userid=2932 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: Reality Check: Power Supplies
I'm cheap so I simply plugged in the SB's power supply to a different outlet. The other equipment is connected to a cheap filtered AC surge supressor strip. I figured this way, any possible switching artifacts would not enter the rest of the system :-) -- crooner crooner's Profile: http://forums.slimdevices.com/member.php?userid=3379 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: Reality Check: Power Supplies
P Floding Wrote: > Adding a filtered power strip (it's the only unit on that strip) to > isolate the SBs power supply from the rest of the system gave a > remarkable improvement Which filtered power stip was it? I know there are some DIY plans out there, and some audiophile versions that cost more than my last car. -- Skunk Skunk's Profile: http://forums.slimdevices.com/member.php?userid=2685 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: Reality Check: Power Supplies
Heuer Wrote: > I am convined as I have tried it! > > My SB3 feeds through a $100,000 hi-fi system and the move to a linear > PSU was very revealing. Made a significant change to the sound (for the > better) and continued to improve as the PSU 'burned in' (and no, I did't > want to believe it either). Standard supply with a high end DAC (Audio > Synthesis DAX Discrete) was the same as linear supply and analogue out. > Add the two together, with lossless encoding (Apple) the sound is on par > with my Theta CD. Still miles off vinyl but very listenable. > > May be different result in other setups but the change is well worth > the $80 invested in the PSU. > > Look at the tests Sean Adams did on the stock PSU and you will see a > spike on the graph which is the switching frequency of the supply. I > know Sean reckons it external noise but I beg to differ! FWIW, I use my SB3 with the original SM supply, feeding an external DAC/Preamp (TacT). Adding a filtered power strip (it's the only unit on that strip) to isolate the SBs power supply from the rest of the system gave a remarkable improvement in sound quality (very unexpected, as I'm using digital transfer). Given this result I would be surprised if a linera supply didn't also affect the sound. My theory is that it is the SM-supply's connection to the mains that gets better filtering now, hence affecting the TacT less. But is is only a theory. -- P Floding P Floding's Profile: http://forums.slimdevices.com/member.php?userid=2932 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: Reality Check: Power Supplies
I am convined as I have tried it! My SB3 feeds through a $100,000 hi-fi system and the move to a linear PSU was very revealing. Made a significant change to the sound (for the better) and continued to improve as the PSU 'burned in' (and no, I did't want to believe it either). Standard supply with a high end DAC (Audio Synthesis DAX Discrete) was the same as linear supply and analogue out. Add the two together, with lossless encoding (Apple) the sound is on par with my Theta CD. Still miles off vinyl but very listenable. May be different result in other setups but the change is well worth the $80 invested in the PSU. Look at the tests Sean Adams did on the stock PSU and you will see a spike on the graph which is the switching frequency of the supply. I know Sean reckons it external noise but I beg to differ! -- Heuer Heuer's Profile: http://forums.slimdevices.com/member.php?userid=2543 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: Reality Check: Power Supplies
Sonic-wise the best way to improve performance would be by means of a higher quality external DAC or analog interconnects. I was never really convinced by the linear power supply upgrades. -- crooner crooner's Profile: http://forums.slimdevices.com/member.php?userid=3379 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: Reality Check: Power Supplies
crooner Wrote: > I am guessing the greatest effect of a better power supply would be on > the analog outputs since these are usually quite sensitive to RFI and > "hash". The digital output's main concern is jitter and I believe the > SB3 jitter levels are already low by design. An external linear regulated supply will reduce the noise going INTO the HV switcher, but it won't make any difference on the noise coming out of the HV switcher and going into the linear regulators that power the analog stages. TD -- tyler_durden tyler_durden's Profile: http://forums.slimdevices.com/member.php?userid=2701 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: Reality Check: Power Supplies
When I first read the title of this thread, I thought that someone had finally realised that you can't turn a SB into a megabucks CDP beater just by adding a external supply. ;-) -- 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=20725 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Reality Check: Power Supplies
jonheal Wrote: > I'm not an electrical engineer, but I know enough to know that noise is > additive (not counting things like out-of-phase stuff cancelling itself > out). If there's more noise when one power supply is plugged in vs. the > other, than the extra noise is the result of the power supply -- > regardless of the preamp's noise level. But what if as I said, the level of the amp noise is such that it masks the SB noise? i.e. can you tell the difference between a xdB level of noise and x+0.1xdB? Paul -- CardinalFang CardinalFang's Profile: http://forums.slimdevices.com/member.php?userid=962 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: Reality Check: Power Supplies
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 -- tyler_durden tyler_durden's Profile: http://forums.slimdevices.com/member.php?userid=2701 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: Reality Check: Power Supplies
P Floding Wrote: > I wouldn't go that far. Sorry. I need to get over the overemphasizing, oversimplification, embellishing, conjecturing etc. They are truly terrible habits, I admit. -- Skunk Skunk's Profile: http://forums.slimdevices.com/member.php?userid=2685 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: Reality Check: Power Supplies
I tend to think white noise is not really the issue. If it increases linearly with volume and has a uniform frequency distribution (and does not vary with frequency), then our brain will subtract it out for the most part. Now, if higher frequencies induce greater levels of noise, or vice-versa, that's more of an issue IMHO. YMMV. RIP. RSVP. (I just love throwing out those acronyms). -- ezkcdude ezkcdude's Profile: http://forums.slimdevices.com/member.php?userid=2545 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: Reality Check: Power Supplies
Skunk Wrote: > Does that translate even indirectly to what people with too much time on > their hands describe as 'inky black backgrounds'? I hope you know I'm > partially kidding Jon! Well, I'm gullible enough that I will go along with just about whatever escoteric mod the Intelligentsia says works -- as long as it costs less than $20.00 ;-) In the case of this power supply/choke debate, I think I am fairly sensitive to subtle grunge noise in my system. In fact, I was detecting a little, and I wondered if it was attributable to the switching power supply. As it turned out, the mechanical source selector on my ancient preamp must have had a little junk in it, because I turned it back and forth fast a few times, and the noise went away. But it did get me thinking about some sort of empirical test to compare the two styles of power supplies on the merits of the noise they inject into the signal path. I have a linear supply that I bought on eBay. Actually two came with my order, so I have an extra. I don't know a thing about them other than the seller claimed they were linear supplies. They produce 5V @ 2500mA. They're huge. They're big grounded suckers that weigh about three pounds. But I need to find a power adapter plug that will fit the lead coming out of the supply and the SqueezeBox, which I believe takes a size "N." -- jonheal Jon Heal says: Have a nice day! http://www.theheals.org/ jonheal's Profile: http://forums.slimdevices.com/member.php?userid=2133 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: Reality Check: Power Supplies
jonheal Wrote: > My experiment focuses on only one characteristic -- audible noise. Power > supplies may have other characteristics that make one more suited to > powering audio components over another. But if one's goal is to simply > inject as little noise into the chain as possible, this experiment may > tell you which power supply is better in this one regard. That's not enough. As someone else pointed out, how a power supply behaves under load is much more important; current delivery, distortion, etc are where power supplies differentiate themselves from each other. -- PhilNYC Sonic Spirits Inc. http://www.sonicspirits.com PhilNYC's Profile: http://forums.slimdevices.com/member.php?userid=837 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: Reality Check: Power Supplies
Hi Jon, You're describing a "blackness" test. A very valid test, but one of many that may be used to decide which PS is better than another. I'm not an EE either, but the gist of the linear PS preference is that the switching supply introduces distortion while playing. So the switching PS could actually be "blacker" but one might still prefer the linear supply for listening to music, because the noise introduced is insignificant at listening levels, while the distortion introduced may be more significant. -Dan -- dwc dwc's Profile: http://forums.slimdevices.com/member.php?userid=1892 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: Reality Check: Power Supplies
Skunk Wrote: > I'm afraid the scientific field fails to explain the hi-fi phenomenon in > general though. Otherwise we'd all be using zip cords of the proper > guage for speaker wire... I wouldn't go that far. After all, our current technology is created through science and engineering. I do agree though that some qualities are not simple to pin down with measurements and specifications. I put most of that down to unaccounted for effects that come into play whenever you start hooking up things to each other -but that is just my pet theory. Keeping this theroy in mind when tweaking the system works pretty well for me though. Another pitfall is relying dogmatically on "truths" about our hearing capabilities. -- P Floding P Floding's Profile: http://forums.slimdevices.com/member.php?userid=2932 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: Reality Check: Power Supplies
jonheal Wrote: > My experiment focuses on only one characteristic -- audible noise. Power > supplies may have other characteristics that make one more suited to > powering audio components over another. But if your goal is to simply > inject as little noise into the chain as possible, this experiment may > tell you which power supply is better in this one regard. Does that translate even indirectly to what people with too much time on their hands describe as 'inky black backgrounds'? I hope you know I'm partially kidding Jon! -- Skunk Skunk's Profile: http://forums.slimdevices.com/member.php?userid=2685 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: Reality Check: Power Supplies
Skunk Wrote: > Is the load presented to the power supply not affected by musical peaks? > Surely not as much as in power amps, but I'm *guessing* listening to > silence would be inconclusive. My experiment focuses on only one characteristic -- audible noise. Power supplies may have other characteristics that make one more suited to powering audio components over another. But if your goal is to simply inject as little noise into the chain as possible, this experiment may tell you which power supply is better in this one regard. -- jonheal Jon Heal says: Have a nice day! http://www.theheals.org/ jonheal's Profile: http://forums.slimdevices.com/member.php?userid=2133 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: Reality Check: Power Supplies
P Floding Wrote: > I'm afraid only "common sense" doesn't really work when it comes to > engineering. I'm afraid the scientific field fails to explain the hi-fi phenomenon in general though. Otherwise we'd all be using zip cords of the proper guage for speaker wire... -- Skunk Skunk's Profile: http://forums.slimdevices.com/member.php?userid=2685 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: Reality Check: Power Supplies
jonheal Wrote: > Since I'm not an electrical engineer, may logic may be flawed, but > here's my proposition as it concerns switching vs. linear power > supplies, and also choking the power cord with a ferrite core: > > My assumption is that whatever noise/coloration/etc. the power supply > is going to be adding to music will be evident whether the SqueezeBox > is playing music or not, because, well ... the power supply is always > supplying power. > > To compare power supplies, I suggest turning the volume up to max on > the SqueezeBox -- not while your playing music, mind you, but while the > SqueezeBox is idle. Then, turn the volume of your amp up to max. Now, > get a good set of headphones and listen. Even with the quietest system, > you'll hear noise. > > Have your wife or someone switch power supplies, or add and remove the > choke from the power line while your listening through the headphones. > If you can hear a difference, pick the quieter option. BTW, disconnect > your speakers during this experiment. switching power supply sends a > big spike through my speakers when I plug it in and unplug it. > > Also, if you happen the get the White Noise of Death during the > experiment, it'll probably kill you on the spot ;-) > > Comments? Am I a little naive concerning These escoteric issues? I'm afraid only "common sense" doesn't really work when it comes to engineering. Yes, you are "a little" naive! ;-D Regards -- P Floding P Floding's Profile: http://forums.slimdevices.com/member.php?userid=2932 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: Reality Check: Power Supplies
CardinalFang Wrote: > But how do you tell where the noise is coming from? Amplifer noise could > be swamping any SB noise. > > Paul I'm not an electrical engineer, but I know enough to know that noise is additive (not counting things like out-of-phase stuff cancelling itself out). If there's more noise when one power supply is plugged in vs. the other, than the extra noise is the result of the power supply -- regardless of the preamp's noise level. -- jonheal Jon Heal says: Have a nice day! http://www.theheals.org/ jonheal's Profile: http://forums.slimdevices.com/member.php?userid=2133 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: Reality Check: Power Supplies
jonheal Wrote: > > > Also, if you happen the get the White Noise of Death during the > experiment, it'll probably kill you on the spot ;-) ROTFLMAO Actually, this test sounds perfectly logical to me. I have a Benchmark DAC1 on order, with headphone outs, so can eliminate the "cheap preamp" part of the equation. I have both the switching and Elpac linear PSU's to compare. Unfortanately, the DAC1 is on back-order. -- sleepysurf squeezebox2 (with elpac wm075-1950-760 linear psu) direct to amp, 300gb buffalo linkstation (remote flac audio file storage), sunfire cinema grand 200 ~five (vertically bi-amped) driving martin-logan aerius i's, blue jeans cables. 'Click to see pix of my system' (http://www.martinloganowners.com/~tdacquis/forum/showthread.php?t=732) sleepysurf's Profile: http://forums.slimdevices.com/member.php?userid=14 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: Reality Check: Power Supplies
Well I tried it, but with effecient speakers instead of headphones, and I only have the original PS- so I guess 'it' is something completely different ;) I noticed on my system with SB at full volume- no signal, noise couldn't be detected until 3/4 pt on integrated volume control. So I turned volume to 0 (mute) on SB and turned volume on integrated until I heard the slightest bit of noise, which by looking at the analog control was _exactly_ the same spot I heard noise at full volume no signal. Not sure what that proves, except that I'm not a scientist or engineer. It does make me question replacing it, but I wish I had a linear to experiment with as they're so cheap. -- Skunk Skunk's Profile: http://forums.slimdevices.com/member.php?userid=2685 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: Reality Check: Power Supplies
jonheal Wrote: > > To compare power supplies, I suggest turning the volume up to max on > the SqueezeBox -- not while your playing music, mind you, but while the > SqueezeBox is idle. Then, turn the volume of your amp up to max. Now, > get a good set of headphones and listen. Even with the quietest system, > you'll hear noise. But how do you tell where the noise is coming from? Amplifer noise could be swamping any SB noise. Paul -- CardinalFang CardinalFang's Profile: http://forums.slimdevices.com/member.php?userid=962 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: Reality Check: Power Supplies
I'm not sure that noise is the only criterion for choosing between power supplies. For example, I have been told that a battery will give dead silent background, but the dynamics in playing music will be different from an AC-powered supply. Some may prefer the silence, but others may think the sound is somewhat duller. -- ezkcdude ezkcdude's Profile: http://forums.slimdevices.com/member.php?userid=2545 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: Reality Check: Power Supplies
Is the load presented to the power supply not affected by musical peaks? Surely not as much as in power amps, but I'm *guessing* listening to silence would be inconclusive. -- Skunk Skunk's Profile: http://forums.slimdevices.com/member.php?userid=2685 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: Reality Check: Power Supplies
What is wrong with you? Don't you know by now that you aren't supposed to suggest anything related to common sense in an "audiophile" forum? Jeez, if we start with common sense we'll end up sliding down the slippery slope towards double-blind testing, and we all know where THAT will get us! TD -- tyler_durden tyler_durden's Profile: http://forums.slimdevices.com/member.php?userid=2701 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
