Eiron wrote:

Serge Auckland wrote:

I think the nub of your response is that people "believe" things sound
different. It's the same mental process that have people believing in
God, the Tooth Fairy and Santa Claus. They don't have a shred of
objective evidence that things sound different, just their faith.

I'll accept that pots, capacitors, resistors etc. sound different when I
see objective measurements that indicate that there should be a
difference and the results of properly conducted double-blind tests that
show that there was a difference.

So is it not the case that metal film resistors have lower noise than carbon ones,

The difference is less than it used to be. Carbon film has simply got better.

and that this gives an audible and measurable difference in phono and microphone
preamps?

With regard to noise it *can*. It's a question of whether in any given circuit the
excess noise of a resistor plays a significant part in the overall total noise. Often,
resistor excess noise may not be the big issue. Poor quality resistors can also have
excessive popcorn/flicker noise. That applies to poor quality metal film as much as it
does to carbon too.

* Excess noise is the part of a resistor's noise that isn't accounted for by ordinary
thermal noise.

Note that this is a question, not a statement. I haven't measured anything recently.

I have.

Graham