So I have a silly little system in my Scion xB. Right now, i'm still 'testing' the setup before I replace the equipment with better stuff, but I want to make sure everything is going to work the way I want before I spend the $$ So, right now there are some old busted RF 10"s I found in my garage hooked up through a Clarion 7 band electronic eq, and into a RF sub amp. Not sure of the models of any of the stuff off hand... The sub boxes were custom built to fit under the driver/pax seat, and the electronics placed into the storage area under the trunk, next to the spare tire. The idea was a moderate amount of bass, but a completely stealth install... Pics: Now that thats out of the way, onto the problem.... Up until last week, everything was working fine... At this point, I had the system connected to a US amp. I chose the US amp over the RF one because it had more power. But I discovered after a week that it was too large for the area I had, and it was forcing the RCA's to rub against the side of the enclosure, thereby slowly grinding into the RCA wire - causing the sub to short.... So I swapped the amps, and in the process I think I f'ed up something, and the bass seems to clip around 50. It won't hit any lower.... To me, this doesn't make any sense, unless the power of the amp is *that* much less that it can't push the speakers.... Oh, and I did go from 1 channel bridged connecting both speakers, to 2 channels, 1 to each sub.... The RF amp doesn't bridge, for some reason... Although right now it hits harder in the mids/high lows than it used to... So, here's where I need some help... 1. I'm looking for a good sound range testing CD. Something that goes from high to low, that will help me identify the cutoff point, and help me identify any weak sound areas... 2. Any ideas why this would happen with just an amp swap? Could it be a power issue?