Re: Teflon Film Tin Foil capacitors, and Auricaps or others

Patrick Turner wrote:

[snip]

About the same kind of things get said about Auricaps, that after fitting
them they "burn in" and
begin to increase the quality of the sound in subjective ways.
I replaced regular Wima polyprops in a client's preamp recently and did one
channel before the other.
We had an AB test with various music recordings in mono to find if he could
choose which channel had the
Auricaps and which one had the old Wimas ( which presumably were "burned
in" ).
He could not identify better than 50% of the time or say which channel was
better, different, or had the Auricaps or Wimas.
I switched between one channel and the other, asking him to identify where
the "better" caps were or not,
but he just couldn't pick it out accurately. I smiled when he said "that's
definately the better one with the auricaps"
after switching from Auricaps to Wimas.
I heard no changes, it was all fine wine to me.
There would have been no point in measuring the thd of the amps with
different caps because the
thd caused by good quality plastic film coupling caps in high impedance
circuits between
tubes is almost unmeasurable.

Remember, Patrick, the A-B double blind test doesn't work in audio,
because it fails to achieve its primary purpose, namely the "isolation
of a variable." When you switch back and forth, you test two variables,
not one, the capacitor, and the ability of the mind to remember audio
passages. The Boulder amplifier company noted in a letter to the Audio
Critic that when they changed a cap WITHOUT TELLING ANYONE, they would
get tons of letters saying "What did you do, this is great?!", and yet
they knew from actual trials that in AB comparisons, no one could
distinguish between the old and new caps. The letters proved that (1)
there was indeed an audible difference, and (2) that their AB trials --
some of them even double-blind -- were incapable of detecting this
difference. The reason is obvious: By switching back and forth, you test
not only the component, but also the mind's ability to "fill in the
gaps," to remember, when hearing the old cap, the information that was
learned when listening to the new cap.

Perhaps by playing a section of music, say, 6 times in a row, and
switching to the new cap at some point unknown to the listener (after
the 2nd, OR 3rd, OR 4th, etc. time), you will find that the listener can
identify when the switch was made, BUT, you can only play a given piece
of music ONCE. Who knows? Perhaps by performing a test that, unlike the
standard implementation of the double-blind test, you will be able to
identify those componenets that truly are superior -- at least, in
combination (use, as some have suggested, a Teflon first, a Mundorf
last) -- and then make an amp that is far superior to anything you have
made so far. However, note that when a change is indeed detectable, and
initially preferable -- perhaps because it provides information unheard
before -- that over the long term, a change from a good component to a
bad component (or circuit) will result in a less satisfying system,
which is not listened to or enjoyed as much, again, even though the
change to that component or circuit INITIALLY seemed to be an
improvement. Perhaps testing listener's reactions when going both from
cap A to cap B, AND from cap B to cap A (using different selections for
each test, of course, so that you don't wind up accidently, but also
stupidly, SHIFTING from a test of the cap, to a test of the mind's
ability to "fill in the gaps"), will help to identify the "better" changes.

Phil


Thanks for your contribution about AB tests.

AB tests are all I have and AB tests do indicate many listeners cannot discern
which capacitors are being used in an amplifier.

Its as simple as that, and further more I have changed from polypropylene to
polyester
or vice versa nobody has heard any difference to the sound.
Next time you build a speaker crossover, change from a 5 uF bipolar electro
to a plastic film cap and notice the complete lack of sound quality change.

Patrick, did you actually THINK about what I said? If I plug your ears with wax, and then test to see if you hear a difference between amps or speakers, would you consider that to be a valid test? I am not objecting to your using AB-tests, I am pointing out to you that using a TYPE of AB-test that causes, actually forces, the test to shift from being an accurate test of the actual differences between two components (this assumes that you have two components that really do have significant differences), to the ability of a listener's mind to "fill in the gaps" when a less revealing component is substituted, is stupid.

Ignoring Phil Allison's useless, very old debating technique of throwing out a bunch of general criticisms without providing any supporting examples or facts (apparently he can say "that's stupid" and it mystically comes true! I wish he would mystically declare that I'm rich ....), look again at what the makers of Boulder amps said. They found the issue of the STANDARD AB-test confusing, because on the one hand they got your results -- caps A and B could not be distinguished in a normal AB test -- and yet another type of double-blind test, which automatically occured when they changed from using cap A to cap B in their amps without telling anyone, frequently resulted in a ton of letters saying how much the amp's sound had changed.

Scientifically speaking, using the standard rules of logic, it NECESSARILY FOLLOWS from the experience of the people at Boulder that the standard AB test, which switches back and forth between two components when listening to a single piece of music, has a low level of resolution, period. Now, I THINK, given that the normal version of the AB test does allow the listener to memorize the music -- and this next conclusion is NOT something that absolutely MUST be true from the rules of logic -- that the reason for this drop in resolution is because the standard AB test actually winds up testing two variables, not the one it was designed for, namely the actual differences between components, AND the abilty of the mind to "hear" what it has remembered from previous runs, thereby overwhelming the actual data provided to the mind from the ear. In other words, we cannot ASSUME that the mind hears only the data stream that the ear is sending to it WHEN the mind has repeatedly heard both the current data stream (cap A) and a very similar data stream (cap B) before. Does anyone have an INTELLIGENT, scientifically HONEST and VALID objection to that statement?

My proposed solution is simply an attempt, and I'm not certain that it will work, to greatly improve the resolution of the AB test by removing this second variable, by removing the ability of the mind to overide the data actually presented to the mind by the ear. This isn't a mindless "components do too sound different!" rant, it's an honest, serious attempt to provide an intellectually valid assessment of the needs and requirements of accurate testing. If AB tests that really do fully test the real differences between components show that no differences between film caps exist, then I will say that those of us who claim to hear such differences are indeed stupid. I won't be happy about it, but I WILL say it.

Why don't you (and that uselss idiot, Allison) ask yourself a couple of simple questions? One, assume that there really are no differences between caps A and B (hell, just use the same cap in all six runs!); would my proposed test consistently show that differences do exist? I say no. Do you agree? Two, given two caps that really do have significant differences, will my proposed test have at least some chance of reliably detecting that difference? I say yes, although at this point, we don't know for certain whether it will have more, less, or the same sensitivity as the standard AB test. However, IF it turns out that my test does indeed have much greater resolving power than the standard AB test -- due to heretofore unrecognized defects in the current implementation of the standard AB test -- then wouldn't ANYONE designing audio products want to have access to those superior test results? Wouldn't you? Unless someone can prove, using the rules of logic, that my test is inferior to the standard AB test, we really won't know for sure until someone tries it.

Phil



The sound is dertermined by factors of recording standards, room quality,
speakers, source, amplifiers etc, and all the many variables within those
categories
People like to think they hear a difference between capacitors and cables but
when challenged to proove they can detect any difference at all they routinely
fail
to hear anything better than 50% chance would predict.

But where directed to instal whatever capacitors make people happy, then I
always just instal them.

The customer is king.

Customers are not dumb, and generally can discern which system they
may prefer.
Unfortunately, I cannot give them the opportunity to auditon 20 different
output transformers and that number of different amp topologies.
I can only build amps with low noise, low thd, low Rout and wide bandwidth.
I mostly generate sales because what I make sounds better in a total way to what
they were used to.

Many amp makers simply rely on getting the numbers right first.
Tweaking around at the edges with capacitor brands and cables appears to actually
do
an extremely small amount of improvement to the sound.
Many amp makers, perhaps myself included make such fine sounding gear that
usually the changing of caps or cables is simply unecessary.

I have no doubt that using the most expensive caps or cables constitutes
very good engineering practice, and I go right along with anyone who says
that brand X is darn good stuff.
But should they allege brand X is better than brand Y, then sometimes I must
humbly request
proof of their allegations. Where they refuse such proof, and cite all the perils
of AB testing
and its spurious nature, then so be it, I leave them with their refusals and
obfuscations
and proceed to build amps without the benefit of their wisdoms, but with whatever
parts they request,
but otherwise to my own standards which work well and with complexities that are
quite incomprehensible to the vast majority of the most seriously minded
audiophiles.

Its easy to make a triode amp that sounds blameless, regardless of what caps or
cables are used.


Patrick Turner.



"Burn in" when used about capacitors is another phrase which means
that an owner has become used to the pain and expense of changeing coupling
caps, and has
mentally accepted them, like getting used to a new maid, even though she
doesn't work any
better than the old maid.
The same things are said and done with cables and line conditioners and a
few other absurd things
that ppl like to suggest make a difference.

Audiophiles like to credit themselves with super-abilities that us ordinary
mortals do not possess.
They place their hearing abilities above everyone else. In some cases, a
few DO have
better hearing, they understand words of opera and songs better than myself
or anyone else and can hum along
in perfect pitch, and their brain is obviously better connected to the
music than most of
the rest of the population. They even understand the purposes of the
emotional intentions expressed
in the music by the composer. But alas in simple AB tests where they are
asked to identify equipment changes
they don't fare much better than anyone else with supposedly normal
hearing.
I have no problem challenging their sacred cow beliefs so to find truth and
thus be better
equipped to build fine systems for such people.

I have always enjoyed my above clients system with or without his Auricaps.

He has an excellent turntable with hi-end MC which renders vinyl better
than most SACD, CD DVD etc,
and nevertheless has excellent silver disk replay systems.

He is very happy and that's what counts. His system is one of very few I
like listening to
all night, and I would rate it better than my own, but mainly because the
source
devices, ie, silver disc and black disc devices are better than anyone
else's.
Maybe the caps make a difference, but I really doubt it, it could be blind
insurance,
"put in these acclaimed caps just in case.."
Acclaimed by who? where does the BS start? with a bribe of someone in an
audio magazine
to give a good review?

Usually when the guys I know here start raving about capacitor sound they
do so
WITHOUT A REFERENCE SYSTEM FOR COMPARISONS.
So they just change something such as caps without comparing to a second
reference system
and say they hear better sound.

But are they? What is the reality?

I give them full permission to fool themselves, but none to fool me.

I have two complete systems in my lounge, and many comparisons have been
made.
The change from having crossover points in a 3 way speaker system from 1kHz
and 5 kHz to
250Hz and 3 kHz was astounding once I learnt about LCR theory, applied it,
and built
a decent measurement system.
Later when i changed from cheap asian made speaker drivers to SEAS drivers
there was another revelation, and I realised I'd wasted a lot of time on
crap made in China.
The tighter magnetic gap tolerances and cone materials in Norwegian
speakers
resulted in clearer and more precise accurtate music.

Caps and cables have made imperceptible differences.
I tried Allen Wright foil types of interconnects, twisted pairs, no change.

Maybe the system was already as good as it was gonna get.
I hear little difference between good class A tube amps and my class A
mosfet
amps.
I thought I could here something different until I did the careful AB test,
and asked
a couple of other folks around.....
Some SS amps are disgraceful though.....no doubt about that.

Patrick Turner.




No one showed me real measurements ;) I wouldn't care if they are
cleverly disguised inner chewing gum wrappers rolled into capacitor
looking packages. I like how they sound.

And, I know someone who has an Audio Precision system in his home. He
gives me lots of good advice. He never mentions his toy gives him the
insight of God Almighty. Perhaps he is too wise for such silly
posturing ;)

Changing anything in my Audio Dungeon may affect my perception of
Music. I may notice 8^0

Changing nothing in my Audio Dungeon might be good for earnest
evaluations of components, but I Ching is a rascally Coyote ...

I enjoy Music through cheap SS amps and cheap speakers, too. I do not
think they sound the same as my fancy stuff, but, Music hath charms to
soothe the savage technoid.

I enjoy the Quest. I enjoy the comradery. I suffer the neo-wizards
lightly. Forgive them, Father, they just like to talk, too ... just
like me.

Happy Ears!
Al



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