Topic: Carbon Film and Metal Film Resistor?

[Adam Warlock]

I’ve read a lot of thread that upgrading resistor somehow improves the sonic quality of audio gears.
There several types of resistor and two are popular among audiophile, carbon and metal film. I think another type is wirewound but this are BIG resistor 
My question is, Which is better Carbon film or Metal film?
Another question is where and when to use the carbon film, metal film? Do you use the carbon film on signal path and metal film on bias level? How about for the power supply?

Please correct me if my question is misleading, Sorry newbie here lol 


Cheers

[Stark3]

LOL. Like you, I've been reading up a lot on resistors and their effect.
Based on what I've read ...

If we're to describe resistors as to their "sound characteristic" (warm, cold sound) and induced distortion with respect to each other

Carbon composition - warm, distortion high
Carbon film - medium, distortion medium
Metal film - can be sterile, distortion low

High precision metal films (Vishay bulk foil, Vishay mil spec (RNXX), PRP, NOS Holcro) were recommended as plate load resistors or in the signal path in general, tantalum resistors (Audio Note, Shinkoh) as grid stoppers. Cathode resistors could be carbon film or metal film, according to taste. Wirewounds were reported to be great as plate load resistors too, very neutral sounding.

For the power supply, metal films again, from what I've read.

DISCLAIMER : Please take everything I've written here with a grain of salt, as I have no practical experience with it, just research.

[ATJr.]

carbon composition resistors are fine for use as grid (control and screen) stoppers because their non-inductive nature helps prevent spurious oscillations on tubes with very high transconductance, and variations in resistance with age and temperature has little effect on the circuit.........

metal film resistors are fine for concertina phase splitters and plate loads, where we want stable resistance with age....

carbon film resistors can be used where metal film types are used....

when using resistors on tube circuits, i always make it a point to give more allowance for power dissipation, example, i will use a 2 watt resistor even it only 1/2 watt is called for, reason being higher rated resistors operates much cooler....heat is your enemy here....

in general, we do not want the resistor parasitics to influence our circuit.....