Please help how to bias this amp

[fretzburner]

This is my first time attempting to bias my amp.This is Guyatone amp with dual 6L6 output tubes.I am in doubt because my other amp valveking112 use dual 6L6 too and very loud compared to this guyatone amp.This is used and not sure if the bias pot was already messed.Reading some info on the net maybe cathode bias technique will do the job but i am hesitant to do it.I need your inputs guys.thanks


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[fretzburner]

Have another thing to clarify.should i put 1ohm resistor on each 6L6 tubes cathode when there is only one bias pot?Or should i use only one resistor and measure two tubes at once?From what i have read it said measure each tube but how to do it using a single bias pot?Sorry for these beginner questions,just want to learn and experiment my own amp.

[amptramp]

I have taken an amp and added 10 ohm cathode resistors (easier to read the voltage) to each cathode.  I then separated the bias control to have two pots, one for each tube.  This was a Traynor YVM-66 which I converted to sweep tube outputs since the original 6CA7's are getting to be $37 apiece boutique items.  I had to regulate the screen voltages down to 150 volts for sweep tubes as well - this was a moderately elaborate conversion but I can source sweep tubes by the basket.  And the last basket of sweep tubes I picked up was $4 for about 20 tubes.  I wired plate caps to pin 3 of the output tube sockets.  It looks a bit more hardcore with plate caps!  No more worries about high plate voltage, either.  Sweep tubes are designed to take abuse.