[Arny Krueger]

"Audio Empire" wrote in message

On Fri, 4 Mar 2011 06:29:00 -0800, Sebastian Kaliszewski
wrote (in article ):

No. The physics and math tell us what the performance
characteristics of the wire is. And of course,
measurements will tell us the quality of the connections.

The same is true for more complex electronics.

Now physics and psychoacustics predict that all A/D, D/A
and amplifier circuits sound the same given their
parameters are within range.

I disagree. Measurements tell us what some of the
performance characteristics of a electronic circuit will
be and the physics and math will characterize that device
to a certain point.

That point is very well refined.

We use maths to design these devices,
they tell us, for instance, what resistors to use to bias
a transistor for the correct current flow, and to set the
feedback for the gain. Maths tell us, what size capacitor
to use to couple the lowest frequency in which we're
interested from stage to stage. Maths also allow us to
tailor filters to our needs and tell us how they will
perform in the frequency domain.

The mathematics all predict nonlinear distortion, etc.

What the physics and
maths don't predict at the design level (among other
things) is the difference in many performance parameters
between components of different qualities.

Not true. The mathematical models for various qualities and types of
components are known and can be plugged into the circuit models.

For instance,
I can design an all transistor amplifier and get all of
the component values right, and yet ruin the design
sonically, just by choosing the wrong kind of component.

Not a problem for the reasons already stated.

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.

The maths and physics I
used to design that amplifier didn't predict that, and if
I build TWO such amps, one with metal film resistors and
one with carbon comp resistors, they'll sound different
and anyone will instantly tell them apart in a DBT!

I remember what life was like in the days of carbon composition resistors,
and I also remember what happened on the occasions where I replaced carbon
comp resistors with metal film resistors. In general: Nothing. The problem
was not so much what a good carbon comp resistor did, its what happened when
that resistor went into some of its possible partial failure moded.

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.

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.

This is not as cut and dry as it seems. While the laws of
physics will predict that the two types of resistors will
have very different self-noise characteristics, that's
not generally a primary consideration when designing an
amplifier.

Absolute and total misrepesentation of generally accepted engineering
standards, even those long before audiophile capacitor parania struck.

Sure, the designer probably knows better than
to use certain components, and what the results would be
if he did, but the physics behind the design exercise
don't encompass those types of choices. They only predict
such things as frequency response, gain, harmonic and
intermodulation distortion and signal-to-noise ratio
based on the parameters of the components used. However,
change the quality of the components and one can make two
identical amplifier sound different, and that's the
point.

There are no known relevant audio circuit design performance parameters
other than linear distortion (phase and frequency response), nonlinear
distortion (harmonic distortion and IM) and noise. People can pretend what
they want, but any other performance parameters only show up in poorly-done
listening tests. IOW, they are false positives.

[Audio Empire]

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.

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? Tantalums shouldn't be used in audio circuits for a
number of reasons, and you are right, the wisdom not use them is well known
and long established, and I know that. But again, this is an extreme example
to show that component type and quality can change the quality of an
otherwise decent design.

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. 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.

[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.