The first mile: What power stations are best for audio?

[Jud]

I agree with your entire post, except this brief portion. You are making an unwarranted assumption that increased distortion will necessarily be perceived as an impairment. If you had spent many hundreds of hours doing audio restoration work as I have, or if you were a professional recording engineer, especially a mastering engineer, you would appreciate that sometimes adding "distortion" can sometimes subjectively improve sound.

 

It is even possible (albeit unlikely) that converting a file to MP3 and converting it back can subjectively improve it. (Beware, even the same listener with the same equipment may reach one conclusion immediately, only to realize on extended listening that this conclusion was incorrect. ) For this reason in any subjective vs. objective debates it's safest to confine listening tests to perception of differences rather than preferences.

 

My apologies for not being more clear. I mentioned "objective" improvement because I meant to speak there of faithful rendition of the source rather than subjective appreciation of the result.

[Tony Lauck]

My apologies for not being more clear. I mentioned "objective" improvement because I meant to speak there of faithful rendition of the source rather than subjective appreciation of the result.

 

These comparisons can be difficult! Considering that the "source" is a pile of numbers, it doesn't really have any sound. I dealt with this with sample rate format comparisons by starting and ending at a fixed reference format. Similarly, given the equipment and test setup, one could compare DACs if one had a suitable ADC so one could compare analog to analog (starting with a live mic feed or high quality analog master tape).

 

It can get dicey if one thinks he knows what the "source" sounded like. I have heard it said that some of George Szell's recordings on Columbia were excessively bright because Szell insisted on this because of his home playback. Audio Asylum Thread Printer

[Jud]

These comparisons can be difficult! Considering that the "source" is a pile of numbers, it doesn't really have any sound. I dealt with this with sample rate format comparisons by starting and ending at a fixed reference format. Similarly, given the equipment and test setup, one could compare DACs if one had a suitable ADC so one could compare analog to analog (starting with a live mic feed or high quality analog master tape).

 

It can get dicey if one thinks he knows what the "source" sounded like. I have heard it said that some of George Szell's recordings on Columbia were excessively bright because Szell insisted on this because of his home playback. Audio Asylum Thread Printer

 

Yes, I absolutely take your meaning here. Two things make me brave (foolhardy?) enough to talk about distortion in an objective sense:

 

- Jitter is timing inaccuracy, so its products won't be as present if the system operates more accurately.

 

- The jitter products are something added by the recording or playback system, and therefore can be considered not part of the original.

[Daudio]

It can get dicey if one thinks he knows what the "source" sounded like...

I have heard it said that some of George Szell's recordings on Columbia were excessively bright because Szell insisted on this because of his home playback. Audio Asylum Thread Printer

 

I think one can take a lot of that diceyness out by using 'the absolute sound'.

 

And, while I may be misinterpreting you, I wouldn't consider a recording as a 'source'.

[Tony Lauck]

I think one can take a lot of that diceyness out by using 'the absolute sound'.

 

And, while I may be misinterpreting you, I wouldn't consider a recording as a 'source'.

 

I took the term "source" from Jud. The context is truth to what is on the record. I don't believe this concept has any firm meaning however, because there is no defined and standard way to map recordings onto sound waves. However, if the goal is to have great recordings sound great, good recordings sound good and mediocre recordings sound OK, then one can evaluate one's system by using a well chosen set of several dozen reference recordings of acoustic music of types that the listener is intimately familiar with. The outliers, such as the alleged Szell recordings, should not be in one's set of reference recordings. The Mercury Living Presence recordings are on the far bright range of what I would consider acceptable recordings of symphonic music. (Calibration based on row 20 in Symphony Hall, Boston, collection of thousands of LPs, CDs and digital downloads.)

[gmgraves]

Yes! and here you get what you pay for, or to say another way, there is a reasonable price/weight!

 

I think my quote of Nelson Pass above was too subtle: the specific reason that he advocates only buying amps that have an appropriate weight for the price is precisely because it is well known that good transformers, chokes, capacitors etc are heavy! ... and these are the actual key to getting good power not magic wires.

 

 

I knew what you meant. I've talked with Mr. Pass at several "Burning Amp" events, and he thinks that fancy, expensive power cords are a joke.

[sandyk]

I knew what you meant. I've talked with Mr. Pass at several "Burning Amp" events, and he thinks that fancy, expensive power cords are a joke.

 

George

Then obviously he hasn't heard his own 150W Class A monoblocks through the expensive power cords we heard them through at a recent listening session. Like you, I was sceptical beforehand.

However, I doubt that what is heard through VERY different mains voltage supplies, and perhaps different internal power transformers too, would necessarily be the same ? Even the current capabilities of U.S. mains feeds in the house is likely to be much greater than from a 240V AC (typical) 50HZ supply here in Au. ?

 

Alex

[jabbr]

George

Then obviously he hasn't heard his own 150W Class A monoblocks through the expensive power cords we heard them through at a recent listening session. Like you, I was sceptical beforehand.

However, I doubt that what is heard through VERY different mains voltage supplies, and perhaps different internal power transformers too, would necessarily be the same ? Even the current capabilities of U.S. mains feeds in the house is likely to be much greater than from a 240V AC (typical) 50HZ supply here in Au. ?

 

Alex

 

He has no doubt heard his amps in all sorts of situations (duh). The salient point being that you could spend $1000 on either a fancy cable or pretty good isolation transformer, which do you think is better? Now imagine $10,000 on a cable vs power conditioning system, including great isolation transformers etc. Again which is better? Now considering that $100-200 can get you a pretty robust AC cable, are you suggesting that $9800 on power conditioning + $200 cable is inferior to $10000 on cable? or even $9800 on power conditioning + $10000 cable? Not saying that I've heard that but would only listen for free, if convenient, because I do have some faith in both Maxwell and Pass

[jabbr]

I knew what you meant. I've talked with Mr. Pass at several "Burning Amp" events, and he thinks that fancy, expensive power cords are a joke.

 

I didn't clarify myself for you:) He is a great opinion because he has written intelligently on the differences between different speaker cable geometries i.e. not a blind cable denier:)

[jabbr]

I took the term "source" from Jud. The context is truth to what is on the record. I don't believe this concept has any firm meaning however, because there is no defined and standard way to map recordings onto sound waves. However, if the goal is to have great recordings sound great, good recordings sound good and mediocre recordings sound OK, then one can evaluate one's system by using a well chosen set of several dozen reference recordings of acoustic music of types that the listener is intimately familiar with. The outliers, such as the alleged Szell recordings, should not be in one's set of reference recordings. The Mercury Living Presence recordings are on the far bright range of what I would consider acceptable recordings of symphonic music. (Calibration based on row 20 in Symphony Hall, Boston, collection of thousands of LPs, CDs and digital downloads.)

 

Well said, and love that reference, I prefer the 32 row for obvious reasons (jk)

[sandyk]

are you suggesting that $9800 on power conditioning + $200 cable is inferior to $10000 on cable? or even $9800 on power conditioning + $10000 cable?

 

No. I would never suggest that, and I don't believe that you should need to go that far with well designed equipment unless your AC mains supply was extremely poor due to perhaps nearby industrial activity. However, the asking price for a pair of Pass 150W Class A monoblocks would certainly justify them either coming with, or being used with far better than hardware store grade 15A cables and power boards. Australian AC mains plugs and powerboards are VERY flimsy !

You also need to be mindful of the fact that this was through a >$100K system, where the owner can afford to spend that kind of money to obtain further improvements, even if they are only relatively small in their own right.

The use of the UpTone USB Regen and an improved PSU for it, made a far greater improvement than anything else we have heard through this particular system.

[gmgraves]

A

George

Then obviously he hasn't heard his own 150W Class A monoblocks through the expensive power cords we heard them through at a recent listening session. Like you, I was sceptical beforehand.

However, I doubt that what is heard through VERY different mains voltage supplies, and perhaps different internal power transformers too, would necessarily be the same ? Even the current capabilities of U.S. mains feeds in the house is likely to be much greater than from a 240V AC (typical) 50HZ supply here in Au. ?

 

Alex

 

Alex;

 

Like I said, whatever you (or anyone else) has heard wrt mains cables, investing in a good quality medical grade isolation transformer with some decent medical grade mains receptacles fitted, will make any mains cable at any price totally redundant. And for far less money than many of these overpriced cables.

[mansr]

Like I said, whatever you (or anyone else) has heard wrt mains cables, investing in a good quality medical grade isolation transformer with some decent medical grade mains receptacles fitted, will make any mains cable at any price totally redundant. And for far less money than many of these overpriced cables.

 

But that solution won't let you feel as smug about it.

[sandyk]

A

 

Alex;

 

Like I said, whatever you (or anyone else) has heard wrt mains cables, investing in a good quality medical grade isolation transformer with some decent medical grade mains receptacles fitted, will make any mains cable at any price totally redundant. And for far less money than many of these overpriced cables.

 

George

The cheapskate in me wouldn't need to do that Downunder, where our AC power generally appears to be much less of a problem than in the USA. I would use higher quality power boards and DIY a similar length higher current rated, and shielded mains cable.

However, with my own gear which has greater emphasis on the PSU area, I don't feel the need to do any of that.

 

Alex

[gmgraves]

But that solution won't let you feel as smug about it.

 

 

Well, there is that!

[One and a half]

George

The cheapskate in me wouldn't need to do that Downunder, where our AC power generally appears to be much less of a problem than in the USA.

 

Alex

 

Appears, huh, your ticket out if challenged.

[sandyk]

Appears, huh, your ticket out if challenged.

 

I don't know of any fellow Sydney Audiophiles who feel the need to use special isolation transformers.

Some of you in the USA must have pretty poor mains supplies if you need to use them, or your gear has quite poor power supply rejection problems.It's as simple as that.

[eternaloptimist]

That's a very interesting notion. It's one I agree with, but here's the kicker - we are then required to decide just what is an extraordinary claim.

 

People, including electrical engineers, are starting to show measurement differences. And electrical engineers are among the people saying the differences are audible. So who's the onus on now?

 

Frankly, I don't think that last question is a particularly interesting one. It's more a lawyer's question than a scientist's. What I'm interested in is what's coming next. Will we see some measurements that demonstrate differences of a type and quantity that should be audible, or not? The anticipation is exciting.

 

Are you serious?? Claims that USB cables / conditioners etc. make any audible difference when blinded are about as far from acceptance in mainstream electrical engineering as you can imagine.

 

I would be very, very interested to see these measurement differences you refer to that are audible. Have you got any links?

 

(Currently pulling out my remaining few head hairs in despair...)

[eternaloptimist]

Bury your head in the sand, and ignore the vast volume of these subjective reports at your own peril. All you need to do is look at the output end of USB cables with a C.R.O , or the +5V wire at the device end, and you will see the effects of SMPS noise etc, that is coupled into the D+ and D- leads, or even low level packets of Data on the +5V wire can be seen when data exchange is taking place. Differential receivers aren't perfect .

 

 

Sure have. That's why I passed some of my findings on to E.E. Martin Colloms and others for confirmation.

 

 

Surely you jest ? There can be vast differences between Preamps and Power amps. At the Sydney listening sessions that I attend fairly frequently, most of the time, more than half those present don't even know which device is actually in use until afterwards. Much of the time, the inactive devices are left powered up to sound at their best when compared, so you can't go by indicator LEDs or displays either .You only need suitable source material from something like "The Storm" from a Chesky Hybrid SACD and good speakers, to hear how one sounds like a storm, but the other makes you involuntarily jump a bit.

One amplifier may even give a realistic impression of height, whereas the other doesn't. e.g. Gryphon Mono blocks vs. Nelson Pass 150W Class A monoblocks. The Pass was WAY more realistic sounding.

 

Ignore "at my peril"?? Or what?? Some audiophile god is going to strike me down?

 

Are you deliberately trying to misconstrue what I said about the hierarchy in my confidence that I could hear (blinded) audible difference in my hifi electrical "chain"?

Just to spell it out:

Speakers: obvious and easy difference blinded. (Otherwise wouldn't have spent >$10 K on speakers). Supported by measurement data.

Pre amp: Probably (otherwise wouldn't have spent $5K)

Power amps. Probably (though not as confident).. as above.

Cables: e.g. Supra USB. Likely not. But is a nicely constructed cable that conforms to standards.

 

I am, however, open to the possibility that any difference I "report" is at least exaggerated by a huge amount of expectation bias and potentially other biases.

 

You, however, do not seem to acknowledge any possibility that what is heard by yourself or others could be psycho-acoustic, or contributed to by these well known biases. Please correct me if I am wrong.

[eternaloptimist]

Error in previous post... couldn't correct for some reason...

Should have read...

....

Speakers: obvious and easy difference blinded. (Otherwise wouldn't have spent >$10 K on speakers). Supported by measurement data.

Pre amp: Definitely (otherwise wouldn't have spent $5K)

Power amps. Probably (though not as confident).. as above.

Cables: e.g. Supra USB. Likely not. But is a nicely constructed cable that conforms to standards.

....

[sandyk]

You, however, do not seem to acknowledge any possibility that what is heard by yourself or others could be psycho-acoustic, or contributed to by these well known biases. Please correct me if I am wrong.

 

I had the same kind of psycho-acoustic rubbish thrown at me for >12 months by a local well qualified E.E. regarding the tests that were performed by Martin Colloms. It eventually took a direct demonstration at his own house, using his own equipment and .wav files that I supplied on a USB memory stick, to result in an apology. On the first occasion he believed he heard differences at the house of another member of our listening group, but after arriving home, and thinking about it more, due to being a qualified E.E. he managed to convince himself that what he heard previously must have been psycho-acoustic. Good old EXPECTATION Bias in play again !

Not long after the session at his own house ,he successfully demonstrated the same differences to an E.E. friend of his, using the USB memory stick that I had left with him, WITHOUT me being present.

Not all members making subjective reports in C.A. are as incompetent as you appear to be suggesting, and many go to great lengths to obtain verification from other technically qualified friends and others, before posting their findings in an open forum.

[trappy]

Yes, people who habitually cite expectation bias never seem to grasp that *knowing* about expectation bias is itself a kind of expectation bias. It makes you think you're the kind of person who can't be fooled. Changes the way you listen. I.e., if you listen skeptically, you will be rewarded, but not necessarily with better sound ;-)

[goldsdad]

Yes, people who habitually cite expectation bias never seem to grasp that *knowing* about expectation bias is itself a kind of expectation bias. It makes you think you're the kind of person who can't be fooled.

 

The opposite can be true, too. For example, knowing about expectation bias makes me realise that I can (and often will) be fooled.

[sandyk]

Yes, people who habitually cite expectation bias never seem to grasp that *knowing* about expectation bias is itself a kind of expectation bias. It makes you think you're the kind of person who can't be fooled. Changes the way you listen. I.e., if you listen skeptically, you will be rewarded, but not necessarily with better sound ;-)

 

Well I listened quite Sceptically to some expensive power cables recently, vs. some from the hardware store, but still managed to hear a difference in favour of the more expensive ones, as did the rest of those present. I didn't wish to believe that amplifiers designed by the great Nelson Pass could possibly sound better with more expensive power cables.

You and a few others, give far too little credit to those members who do accept their limitations, and repeat their observations many times over using non sighted listening tests. Many of us do realise that even things such as your Blood Pressure level at the time can markedly influence results , and take this and many other variables into account by repetitive testing, and involving others in the process.

As a DIY person, I have on quite a few occasions made changes that I thought should improve things, but after serious listening over a period of several days, I have no longer been 100% sure and reverted to the original configuration, only to find that I was mistaken about the previous perceived improvement. This is something that most experienced DIYers are well aware of, and try very hard to take into account.

[eternaloptimist]

I had the same kind of psycho-acoustic rubbish thrown at me for >12 months by a local well qualified E.E. regarding the tests that were performed by Martin Colloms. It eventually took a direct demonstration at his own house, using his own equipment and .wav files that I supplied on a USB memory stick, to result in an apology. On the first occasion he believed he heard differences at the house of another member of our listening group, but after arriving home, and thinking about it more, due to being a qualified E.E. he managed to convince himself that what he heard previously must have been psycho-acoustic. Good old EXPECTATION Bias in play again !

Not long after the session at his own house ,he successfully demonstrated the same differences to an E.E. friend of his, using the USB memory stick that I had left with him, WITHOUT me being present.

Not all members making subjective reports in C.A. are as incompetent as you appear to be suggesting, and many go to great lengths to obtain verification from other technically qualified friends and others, before posting their findings in an open forum.

 

More anecdotes about un-blinded reported differences.

Frankly, I couldn't care whether it was Nyquist himself who was at your house. If the trials were not blinded, then psycho-acoustic differences were not excluded.

Yes, good old EXPECTATION Bias in play again!

If, however, the trials were indeed blinded and your EE friend could consistently pick the difference, then this is genuinely interesting and would be fascinating if it could be reproduced.

 

Note: I am not saying differences could not have been present, but this anecdote does not provided anything other than more anecdotes and is poor quality evidence.

 

If you or anyone wants to report that hardware / tweak "X" sounds better, great! But please do not expect this to be accepted as gospel which cannot be questioned or as more than your subjective opinion.