Cathode resisters for 36Watt
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Cathode resisters for 36Watt
I'm pulling together the bits for a 36Watt head using the AC30/Matchless transformers from Dave West at WestLabs. Thinking ahead, I'll probably be basing the power section on the Hoffman AC30. Meanwhile, I'd like to be able to switch between 2 power tubes or 4 power tubes. In order to do that, I suppose I have a couple of options: 1 cathode resister for each tube or 1 cathode resister for each pair of tubes. If anybody has any advice on which method to pursue and what values they'd suggest trying, that would be great. Also, I'm not sure if the filtering needs to change since this is a 36Watt. Do most folks keep the same 18Watt filtering in place for their 36Watters? Thanks!
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There are probably a few different ways to go about the cathode and screens.. 1, 2 or 4 resistors could be used for the cathodes,depending on what you want,and change the values to how many you use. I think for half power,we had talked about this earlier..to keep the voltages pretty much the same..it would be best to cut or ground the signal to one set of the EL84s..
Graydon does use different filter stage values and resistors for his 36..and uses 4 cathode resistors if i remember correctly and no choke..
My 36 uses the choke,and 2 cathode resistors one for each set of EL84s..
But it is a TMB amp..if you stick with the Stock amp circuit,and just make it 36 watts,then probably don't use the choke..
Richie
Graydon does use different filter stage values and resistors for his 36..and uses 4 cathode resistors if i remember correctly and no choke..
My 36 uses the choke,and 2 cathode resistors one for each set of EL84s..
But it is a TMB amp..if you stick with the Stock amp circuit,and just make it 36 watts,then probably don't use the choke..
Richie
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