Why does this happen with *most* two channel amplifiers? I have a Punch 150 run it bridged to a 400 single voice coil sub it's 4-ohms. So I don't know why it gets hot. But this is not the case. I'd like some information on these type of things. Oh yeah it starts to get hot after maybe around 10 - 15 minutes of listening time. I'm not one who blasts it constatly, just to get some bass going on.