SWR Stereo 800 - Bias adjustment

[stereomonostereo]

Hey guys,

I just finished rebuilding one side of a badly blown SWR Stereo 800. She's up and running, but I want to make sure that the bias is adjusted properly. Does anyone happen to know the proper setting that these want to see? Thanks in advance!

[Enzo]

Proper setting is to feed a sine wave through it, watch the output and adjust the bias until the crossover notch JUST disappears. Then back off just a hair.


A quick and dirty method is to watch mains current draw for the whole amp. Start with the bias coldest, then turn the control up until at some point the mains draw will start to rise with the adjustment. That start of current rise is the point to stop, then back off just a hair.

[stereomonostereo]

Thanks Enzo. What's the best method to measure the current draw? And when watching the current draw, should I be running a signal through the amp, or can I do it without?

[stereomonostereo]

Apparently my meter's amperage function isn't up to snuff. I hooked up my backup and that read fine. Thanks again Enzo, you're a lifesaver

[Enzo]

Mains draw is power from the wall outlet, you put an ammeter in series with the hot lead of your power cord.


The power draw method is done at idle. The crossover distortion method of course must be done with signal.