Tw bias pot
Moderators: pompeiisneaks, Colossal
Tw bias pot
New to amp building.why do most tw amps I see have bias pot on board is this a sound or tone thing or looks .. I am building a tw when parts show up .. I would like adjustable pot and bias test points out side amp is this a no no ... I have done this to all my old fenders did not sound like it messed up the tone? And any tips on building this particular amp it is the express with el34
New Amp maker
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Stevem
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Re: Tw bias pot
You can mount/ place a bias pot anywhere you want in a amp, the - voltage feeding and out of it will have no effect on any other circuit.
The test points if feed off of the output tube cathodes should be kept near the output stage and away from the preamp section.
The test points if feed off of the output tube cathodes should be kept near the output stage and away from the preamp section.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: Tw bias pot
There are those who believe strongly that providing for a B+ (high voltage) test point on the exterior of the chassis defeats the purpose of the chassis. For that reason, the only recommended test points are for the 1 ohm cathode sense resistors, one at the cathode and the other at ground. Think about this -- someone who doesn't know better sticks something into a test point that has 300VDC or more on it and ends up hurt or worse. And labels don't help because stupid people don't read. If you want to read plate voltage, pull the amp from its case. Be safe!