that thing from radio shack was just too much trouble. now, what's the best way to use my amp with this thing? i like an uber-distortion sound and from what i've read, i want to get that from the power tubes. what volume settings should i use? i've got the gain, the master, and the lead master volumes.
I'm not sure what amp you have, but set your master volume to max (usually they just attenuate the signal going to the power amp).

Play around with your settings, you should be fine.
Just mess with the amp, and then adjust the attenuator so the volume is right.
I'm not very active here on UG currently.
I'm a retired Supermod off to the greener pastures of the real world.