j.pagejr.
stiff
Join date: Jun 2007
10 IQ
#1
hey guys,

Need to rebias my amp, don't ask why..Anyway everywhere I've looked the output wattage has been different for the Sovtek 5881wxt's. Somewhere was 20.5W another 23W and another 25-26W?? I know I need to calibrate them for 60% at idle but I dont know what to aim for??? help would be appreciated, also when biasing am I running the amp w/ the volume at 10??

EDIT: Oh almost forget, we're talking about a '73 super reverb..... thanks in advance!
cheers betch
Last edited by j.pagejr. at Mar 25, 2013,
311ZOSOVHJH
G G A - B A B Y
Join date: Mar 2008
750 IQ
#2
All power tubes vary like that. Not a big deal. That is why it is so important to get matched sets.

Also, you don't HAVE to go for a plate dissipation of 60%. I have a feeling you are getting too hung up on the numbers. People should bias their amp to the best tone. Volume should be on '0'.

So why do you need to bias? That was a joke . But seriously. Just curious. Do you need new tubes or is there something else going on.

Actually the bigger question is why are you buying Sovteks?
Cathbard
Grumpy Old Tech
Join date: Oct 2009
240 IQ
#3
You're using a bias probe? Aim for anything between 60% and 70% and you'll be fine. There's a lot of room for error. So between 13.8W and 16W will be fine.
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j.pagejr.
stiff
Join date: Jun 2007
10 IQ
#4
Well sovteks were already in the thing when I got it. Accidentally turned the bias pot and threw it all off. Not using biasing probes cause I needed to get this done yesterday- can only find them online. Thanks for the help though
cheers betch
Tremolo Bum
Addicted to FR
Join date: Feb 2008
130 IQ
#5
Does it sound bad? As long as the tubes aren't red plating you're fine. If they're biased too hot it may shorten the tube life a bit and if they're biased too cold you might hear worse tone, but won't damage anything.

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