[Arny Krueger]

"Audio Empire" wrote in message

On Sat, 5 Mar 2011 08:33:54 -0800, Arny Krueger wrote
(in article ):

A high gain stage might call for 33,000 Ohm resistor.
OK, fine. I'll use a 33,000 Ohm resistor. But if I
choose a carbon composition resistor instead of a metal
film, that high gain stage will be noisy.

You're joking, right? Nobody is using carbon composition
resistors these days.

No, I'm not joking. I was using an extreme case to make a
point, and that SHOULD be obvious to even the most casual
observer. Of course, nobody uses carbon comp resistors
any more, but if one did use them throughout an amp
design, that amp would sound different from one using
metal film resistors.

That is a claim that I have personally falsified. In almost every case a
properly operating carbon comp resistor in audio gear causes no audible
difficulties, either on the grounds of noise or nonlinear distortion. I have
actually replaced every carbon comp resistors in a number of audio
components (amps, preamps) and listened to and measured the differences.

Same
thing with capacitor selection. If my design called for
a a series of coupling capacitors capacitor in the
signal path and I used tantalum capacitors in those
spots instead of a some kind of low DA film capacitor
like a polypropylene or a mylar film capacitor, the amp
circuit is going to sound different than it would had I
used the low DA types of capacitors.

Same story. I even had a well-known capacitor dielectric
maven whose named rhymed with bung send me some good and
bad capacitors to try in some projects. The so-called
bad capacitors were simply not the part that long
accepted wisdom said should be used in the application.
The good capacitors were film capacitors but in actual
use there was no measuable or audible benefit as
compared again to what long accepted wisdom said should
be used.

IOW, Walt sent you some tantalums (or maybe some
aluminum) electrolytics and some Polypropylenes?

He sent me Hi-K ceramics and and polypropylenes to be used as coupling
capacitors.

Tantalums shouldn't be used in audio circuits for a
number of reasons,

This is false. Tantalums cause no audible or measurable problems provided
they have appreciable DC voltage across them. IOW they work well in audio
components with single-ended power supplies.

DA is important in sample-and-hold circuits and afew
other applications. The fallacies associated with audio
enthusiast misunderstandings of DA have been explained
well by well-known and highly regarded experts such as
Robert Pease of National Semiconductor.

I know that he disagrees with Mr. Jung et al on this
issue, but blind tests between two Hafler preamp kits,
many years ago, one wired per the factory, and the other
wired with "Wondercaps" in place of the factory supplied
capacitors, showed conclusively that the "Wondercap"
wired Hafler sounded much cleaner than the one wired with
the factory caps.

I know of only listening tests whose results were contrary to that. Probably
just another poorly-done single blind (i.e., defective double blind)
evaluation.

In fact its hard to find measurable differences in that situation, let alone
audible ones.

That and an experience where I replaced
the Mylar film caps with "Wondercaps" in my Magnaplanar
Tympani 3Cs (the ones with the eight panels) showed me
conclusively (as far as I'm concerned) that Jung was
correct about capacitor sound.

The hidden agenda in upgrades like this is that the capacitance of the
capacitors and other traditional parameters such as ESR no doubt changed.
The ESR of parts like these are calculated into a well-done crossover
design. In the case of one well-known anecdote relating to Maggies, the
original parts were not soldered in, but the replacements were.