Revalve a quatravalve

[andytoad]

Hello all,
I'm tempted to revalve my trace quatravalve. I can't see any pots to balance them, would they be self adjusting?

Never changed them before....

[Roland Rock]

Hi Andy, I'm interested in this too, as I have the Twin Valve. This thread on TB concludes that the QV is fixed bias:
http://www.talkbass.com/forum/f15/trace-elliot-quatra-valve-165731/index2.html
if so, so you'd need to get a tech to do it for you

Edited April 15, 2014 by Roland Rock

[VTypeV4]

So it's likely our TwinValve rigs are too?

[andytoad]

[quote name='Roland Rock' timestamp='1397541231' post='2424867']
Hi Andy, I'm interested in this too, as I have the Twin Valve. This thread on TB concludes that the QV is fixed bias:
http://www.talkbass.com/forum/f15/trace-elliot-quatra-valve-165731/index2.html
if so, so you'd need to get a tech to do it for you
[/quote]

Ahh,
Does that mean they need to change resistors on the powerstage to balance them out?

[Roland Rock]

Sorry, not sure. I just know that my Red Iron amp is fixed bias, and I need to take it to my tech for adjustment when changing the KT88s. I have no idea what he actually does :-)

[Matte_black]

Because of the high voltage in tube amps and the fact that resistors can store high amounts of electricity for long periods, I'd avoid the risk and would pay a tech to do that. Expecially 'cause a once over can certainly make you save money on the long run, there are many small/cheap components in a tube amp that gradually die and of course they can bring around lots of expensive parts if neglected... just my 2 cents.