Biasing Amps

WARNING - All modifications involve you being in the vicinity of dangerous voltages that could easily kill you if you do not follow safety procedures and are not qualified in the Electronics industry. We accept no liability whatsoever for your own actions and subsequent demise should you not follow current safe practising skills where hazardous voltages are present.

Why bother I hear you ask?

There are many reasons why you should bother - none less than your tone, guaranteed to suffer through a tube amp if the amp is not biased properly for the power tubes - it's that simple really.

Consider this, if I said that your fender guitar sounds like a les paul then no guitarist in the world would agree (likely) - then ask ANY amp technician if the amp will sound right with incorrect bias adjustment - none of those guys would agree either (very likely).

Tube amps are made that way. It's a sort of balancing up of the tubes electrically and this balancing helps the tubes to work together inside the amp. The alternative is tubes that effectively run too hot or too cold - both affecting your sound. The manufacturer has designed the tube amp with an optimum bias and taken that in to account at the design stages, so any thing different will yield a different sound than intended - you WILL tell the difference, make no mistake.

Badly biased amps can often shorten the life of the tubes considerably and that hurts today in your pocket - especially if the failed tube takes out a transformer - or burns the boards, or.... well you get the picture.

There are a few ways of biasing an amp, but if you hate electricity don't try - it could easily kill you - the voltages inside are lethal. Biasing is sometimes discussed on the net, but when I went looking I was surprised just how little info there was and how misled some users were about this important setting for your tone.

Later amps like the TSL100 are easy to bias, mesa are generally fixed, but earlier amps can be a pain.