Bill - Though it may sound complicated, it really is very simple. Once you've done it once or twice it'll be a snap. I don't know the Stax procedure either, but most manufactures give you easy access to the points you'll need to read and change the bias. BTW, many modern tube amps now use some kind of auto-biasing circuit eliminating the need to bias. Here's the basic procedure (trying to simplify for newbee, though it really is pretty simple): Get yourself an inexpensive digital multimeter from Radio Shack that reads in milivolts. Turn the amp on with the headphones (speakers in the case of a regular amp) connected, the volume turned all the way down, and no source connected to the amp. Let the amp warm up for 3 minutes or so. Each tube will have two contact points to take a reading. Set the multimeter to read mV and use the +/- probes to contact the two points for a single tube. This will give you a reading on the multimeter which may or may not be close to what you are aiming for. You will need to know exactly what the manufacturer reccomends for that amp for optimum performance (as Swampwalker said, a manual will be very helpful through all of this). Let's say it is .37 and your meter reads .49 - this would mean your bias for that tube is too hot and you need to lower it. To change the bias of the tube there should be either a knob, or more likely a screwdriver slot, in which case you'll need a small screwdriver. The knob/slot is connected to the pot(entiometer) Swampwalker was talking about and is there to adjust the bias. With the meter still touching the two points readin the bias of the tube, turn the screw quite gradually counterclockwise to lower the current (bias). You will see the numbers go down. Get the number to come as close as you can to .37 (or whatever number the manufacturer recommends as the bias point). Usually there is a tolerance of a few milivolts, and it will fluctuate/drift a bit, so just come as close as you can and don't worry about it. Go to the other tube (you only have two) and repeat the procedure with the proprietary pot and reading points for that tube. Once you've done the second, you may want to go back and check the first and re-adjust, and do the second once more too. After that, you're done. You should probably check/adjust the bias once a month or so. Again, once you've done the procedure once or twice it's a snap. It definitely is not time consuming for two tubes. First time will likely take all of twenty minutes perhaps since you'll be learning by doing. After you get it down you'll be able to do it in five minutes.
Marco
