mudaholic

whats up all.

i finally got some time to work on my stereo, and i got everything installed and all, but now i got some troubleshooting issues.

when i turn on the cd player (kenwood excelon kdc-x917), all my speakers/subs start popping, about once per second (with the car off). if i disconnect the rcas from the headunit but leave them plugged in at the amp, they pop at about half the previous volume. if i screw around with the ground for the amps it also helps a little bit. but, theres still popping.

the resistance from the amps to the ground location is 0.3 ohms. the resistance from the grounding bolt to the negative battery terminal is 0.4 ohms. so, the total resistance from the amp to the negative battery is 0.7 ohms. also, i have 13.4 volts at the amp's positive terminal (with the car off).

also, about every 5-10 seconds one of my amps (jbl bp180.2) goes in to protection mode for about 1 second and then powers up again. 5-10 seconds later it repeats the cycle. changing the grounding point does nothing for this, nor does relocting the amp. it is not touching any metal of the car. the other amp (jbl bp1200.1) does not have any protection mode problems. (also, the 180.2 is VERY hot after a couple minutes of playing at the lowest volume setting (1 out of 35), hot enough that i can only touch it for about 10 seconds. i dont recall any of my other amps ever getting that hot, but maybe its normal for this one...)

anyway, i've spent as much time as i can on this for now, being finals week and all. any input would be greatly appreciated. thank you.

joezero

The fact that the amp is getting really hot means one of two things is happening. 1. There is a short inside the amp. 2. There is a short in a speaker or wiring.
What I would do is disconnect all the speaker wires at the amp. Then get a known good speaker and connect it to the amp and try it again. If there's still the popping and overheating, it's a problem with the amp and take it back. If the problems go away, then pull all of the speakers in the car that are normally connected to the amp. Using a short piece of speaker wire, test them. If you find one that makes the popping or overheats the amp, throw it away. If not, then run new speaker wire for the speakers and try it again.

mudaholic

i will check that out, one thing to keep in mind is that all the speakers in the system are popping, even the subs connected to a different amp. a defective amp shouldnt be screwing around with speakers that arent even hooked up to it. but, i will try another speaker to make sure that nothing is shorted out.

joezero

If all of your amps are sharing a grounding point it might effect all of them. When I read through your first post, I thought it was a grounding issue, but you mentioned you changed the grounding point without success. But do the amps ground at the same location and/or through a grounding block?

mudaholic

yes, both amps are grounded to the same spot. the resistance from the negative terminal on each amp (ie before the grounding point) to the negative post on the battery is 0.7 ohms for each amp.

joezero

I would be surprised if the resistance was any different, but you could be getting a ground loop. I would try running your system with just one amp grounded at a time and see if that does anything.