Resistor types in an amplifier

[pforeman]

All my parts are ordered, and installed in my simple se. However, I was wondering, when looking at Georges parts list, is there a sound difference in wirewound, metal film etc, or are you simply interested in ohms, and watt rating
thanks,
Paul

[ChrisA]

Originally posted by pforeman
All my parts are ordered, and installed in my simple se. However, I was wondering, when looking at Georges parts list, is there a sound difference in wirewound, metal film etc, or are you simply interested in ohms, and watt rating
thanks,
Paul

There are very small difference in the sound. The reason is that none of the resistors are "perfect". Some have inductance and some have non constant resistance value.

Older carbon comps will change resistance value based on voltage across terminals. I just read a calculation that under "ideal" conditions this can add as much at 10% 2nd harmonic distortion to an amp. BUt that number is a cooked up worst case, normally the effect is way less than 1%. And nobody uses CCs anymore except sometimes in guitar amps. The differences between the other types are less. Mostly the difference is in self-noise and inductance and availability of the type in the value required. I looked at his parts list too and my guess is that he selected them for lowest noise.

[Gordy]

It depends upon application and suitability of characteristics. For example if you had an application where current of any size is to pass through the resistor you would want to avoid carbon composites as they tend to generate more noise. However in low-current positions where you need a non-inductive resistor then carbon would be fine (such as grid stoppers for example).

You can forget all that nonsense about 'resistor sound quality' because components do not have, and never will have, a sound quality. What they have are electrical characteristics that you must select and apply according to the needs of the application.