Metal Film Resistors for audio

[MarcelvdG]

The late @DF96 and @GoatGuy would disagree.
https://www.diyaudio.com/community/threads/tube-amps-and-resistor-composition.343652/post-5938153

If the grid stopper resistance is large enough to get rid of any negative resistance, then the inductance doesn't matter. By the time I understood that, DF96 had deceased.

 

[Rod Coleman]

If the grid stopper resistance is large enough to get rid of any negative resistance, then the inductance doesn't matter. By the time I understood that, DF96 had deceased.

Yes!

Negative resistance (looking into the grid) can certainly provoke oscillation for cathode followers.

In other circuit configurations, some form of Hartley or Colpitts oscillator is also likely. In this case, the grid stopper acts to spoil the Q of the the tank circuit; again, a little inductance in the stopper will not cause any problems.

 

[Mark Tillotson]

My rule-of-thumb figures are 17 nH and 0.25 pF for a through-hole 1/4 W carbon film resistor, values coming from an old Philips databook. 1/2 W or 0.6 W metal film should be of the same order.

To put that into perspective that's less inductance/capacitance than the wiring or PCB traces in most situations. At 10MHz 17nH is an impedance of about an ohm, at 10kHz its 0.001 ohm. And SMT resistors are far better still!