tested a crossover, now amp cuts out?

I have a 97 Maxima, and I have an Alpine CDA9827 headunit, Alpine MRD-M500 hooked up with cap, and Alpine MRP-F240. Everything was working great, except that there was no crossover on the amp, just highpass/lowpass. So my friend had an MTX LSX2 (I think was model number) crossover, but wasn't sure if it worked or not. I hooked it up, jumping power/ground/remote from the 4 channel to the crossover, and hooked up the RCAs (all rcas were in working condition). Sounded great for a while, crossovers worked well and cut out all the bass, giving me exactly what i was looking for. So I left it alone thinking everything was fine. A few days later, the highs started cutting out at high volumes, and the rear channel wasn't working. thought it might have been the crossover, so hooked up just the amp, and the rear channel was fine, but highs were still cutting out, and this time at a lot lower volume. At first the volume was at 17, now it will cut out when volume is at 11. I am baffled because the first day I was cranking it around 20 and it was fine. Now my question is, what happened? I eliminated the crossover for the cause of the highs cutting out, so is it the amp or the radio? Any ideas or suggestions would be greatly appreciated. Tomorrow I am probably going to try to hook up another 4 channel, to see if I can find out what is actually causing the problem.

Could be a number of things, but it sounds like the amp may be having problems.  Did you carefully match the input gain to the crossover output voltage?  It is possible the crossover has too high an output for the amp and has fried the input stage, although this is relatively rare.  It's also possible you simply have your gain too high, or the impedance load on the amp is too low.  Make sure none of your speakers are shorting out, and that the total impedance load per channel is greater than 2 ohms.  By the way, the "lowpass/highpass" filter on an amplifier IS a crossover.Support the12volt.com