O.K. I would love to get feedback from others on which amps have the tightest lows. I am looking for a very non-tube like sound. In other words, a slightly stiff sound. I like to solo the bridge pick-up on my jazz bass and crank the bass knob up high. I find that real tubey amps just get muddy when you crank the bass up, even though their flat sound "sounds" deeper, due to the rounding effect of the tubes. I am currently using a GK 1001 RB, which I am actually quite happy with. However, when I read all the buzz about Euphonic Audio, Thunderfunk, Walter Woods, Markbass, etc., the grass starts to look a little greener. Unfortuneately, I know of no dealers in Pittsburgh that stock any of these amps, so I have had no chance to try them.