[quote name='lefrash' timestamp='1350038615' post='1833795']
I have an LH500, and I've never once had any sort of grind from it at all. Its easily the cleanest amp I've ever used.
[/quote]
True dat, if you've got some distortion then plug your bass into the 'active' socket (assuming that you don't want distortion, that is), occasionally on board Pre's can overdrive the tube in the preamp stage, but only very rarely.
One curious thing about these amps is that the EQ section has a 'built in' mid scoop with all three knobs set to 12 o'clock. I think to get a (nearly) transparent sound from the amp the bass has to be at 10 o'clock, mid on full and treble all the way off IIRC.