right, playing with a mel c track with infrasonic bass, I can cause something to distort badly, its not hi freq. I think I may have an idea, but its not the amp certainly, I tried the 450 watt crest, and it has clip indicators which aren't lit when it happens, so that rules the amp out. so its either the cd player output stage perhaps or.... I think the coil of the loudspeaker bass unit is excursing too much, jumping out of the magnetic gap causing massive distortion. Strange as they are morel drive units, but only 5 inchers in a transmission line, so its not the drive units fault perhaps apart from being too small, more the loading methinks. I can still get a lower power amp to clip anyway which complicates things. What do peoples think? I quite like the sonic maximiser btw, its arrived, and is a bit like a subtle loudness control in it works on the bass and top, it adds sparkle without harshness and doesn't degrade signal at all....has a bypass and doesn't gain detail and all that. its programme dependant, speaker dependent, too, different settings needed, but is useful, without it music is smoother and natural, but its not too processed. Got to get a stereo image processor to play with soundstage now, too.