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Which resistors to use for KT88 output tubes

Hi, I'm looking for 5 watt 10ohm, 100ohm, and 2.2kohm resistors to use on the grid, screen, and plate of the KT88s in my amp build. I've looked into Kiwami, but most seem to feel Mills are better for this application. The Mundorf M-Resist Supreme resistors seem even better, but the largest value Mundorf is 33ohm. Any advice or other alternatives? Has anyone compared these resistors? Thanks.
dracule1
rodman99999
6,108 posts
 
Metal films like Vishay and Caddock, are excellent, but good wirewounds have actually proven to be quieter. ( http://www.aikenamps.com/ResistorNoise.htm ) It can't hurt to have stable/quiet resistors, in every section of your circuit.
dracule1 OP
1,085 posts
 
Hi Rodman, I don't see any mention of wirewound resistor being quieter than Vishay or Caddock in the link you provided. Is this from your personal experience?
rodman99999
6,108 posts
 
Again, the Vishays and Caddocks I was referring to, are both Metal Films. Read the paper again, in that light. Yes, this has also been my experience.
dracule1 OP
1,085 posts
 
Wont metal film work just as well on the grids?
dracule1 OP
1,085 posts
 
Thanks Rodman. I read it again and saw the reference to wirewound resistors.

Based on the schematic of my KT88 amp, I see a 2.2 kohm 2 watt resistor to the control grid, a 100 ohm 5 watt resistor to the screen grid, and 10 ohm 5 watt plate resistor.

Obviously, the 10 ohm resistor should be a wirewound resistor. It will probably also be noninductive as well.

The control grid resistor should be a noninductive wirewound too.

It is the screen grid resistor that should be carbon comp because of its low inductance? Why can't I used a non-inductive wirewound resistor here?

PRC makes very high quality precision wirewound non-inductive power resistors.
http://www.precisionresistor.com/files/PDF/Precision-Power-SM-Series-Wire-Wound-Precision-Resistor.pdf
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