But.the amp will work and the sound that is created may please the player’s ears. The problem with this ‘biasing with eyes and ears’ is the same problem with biasing without knowing the plate voltage.one does not really know where the tubes are operating. My ears will put the amp somewhere in the 55-65% of max plate dissipation range, ime. The advantage of this system is that it brings the player’s ears into the equation.and that is the ultimate point, correct.sound. Within the boundaries of crossover distortion and imho redplating, one can find what they feel is a good sound for them. , long before that the amp is not sounding as I want it to sound. At some point and if the bias pot allows it, you will cause the amp to incur crossover distortion.things get harsh and imho unmusical. Lower current draw is easier on the tubes. The amp is safe to play at any setting from there on ‘down’.decreased current draw will cause the amp’s Sonics to creased harmonic content. Note: in fix3d bias, current draw increases while signal is being process as compare to current draw at idle. If redplate begins while you are playing, decrease the draw very slightly until,playing does not bring on redplate. If the plates do not go into redplate condition while playing, Back away from that point and play while watching the plates. Once you know that, gradually turn the bias adjustment in that direction until the plates just begin to show some redplating. Increasing the draw will bring on a bigger, richer Sonic. Then, turn the bias pot a small bit and play it to find out which direction one should turn the pot to increase or decrease the current draw. All you need is the amp, a guitar and a tool to turn the bias pot. Okay, I’ll suggest the easiest way to bias an amp.since biasing without knowing the plate voltage is about the same thing.

Bias guitar amp app