I have a chance to buy this amp and was wondering if anyone knew the purpose for the 3 position power switch. Middle is off and up or down powers it up. The amp is in very good condition with 2 Japanese 8 ohm 10" speakers wired in parallel for a 4 ohm load. The amp has two inputs:Volume, Bass, Mid, Treble, Bright, Distortion, Tremola and a Pre-set volume. Someone has done a couple of mods and the reverb doesn't seem to be working but other than that appears to be a very solid amp with a Fenderish sound.