DsevenEm2

The other day my buddy was about to purchase another sub for another car. He brought his car since it had everything already hooked up for testing.

He has a 2-channel amp for his tweeters that was a good match for said tester sub. He disconnected the tweeters and left them there, then made a bridged connection for the sub afterwards.

We hooked up the new sub (Kicker L5) to this amp in bridged mode. The kid had no idea how he had the coils hooked up (in series or in parallel, and we were actually confused as well)..

So we tested the sub and it sounded like garbage. There were two of them, I'm sure the second one sounded worse because the soldered coil connection to the sub was snapped off (just one)..

Anyway he suggested that our amp was no good, and to connect it to the other amp we had, that was supplying power to the subwoofer my friend had (kicker cvx). Now that amp was rated at 750 watts RMS and this kids some was rated at only 600 RMS. Anyway we connected it, didn't make a difference and that was it.


---- Now after he left we reconnected everything, we have a high pitched wine on the tweeters and the sub is rumbling constantly. Like its getting too much amperage to it.

By the way we had hooked up those tweeters just a week before, and the amp that powers those, we used the same ground post as the amp for the sub. It had been working fine, up until we tried hooking up this garbage sub.

Sorry its a long read, but any tips at all?

KRock459

Couple of questions (1) Does the sub rumble increase when changing tracks on CD or changing sources? (2) is the whine from the highs noticed when the vehicle is running?

If the answer is yes to either or both, you have a signal grounding issue. the chances of both amps failing at the same time are not likely, the only common factor is the source. Not sure why a sub could have caused it, but if ground was removed from either amp this would most likely cause this.

Kirk R

DsevenEm2

Well last night we seperated the two grounds and gave each amp their own ground. That eliminated the sub rumbling. And no it didn't increase when changing tracks at the time.

That fixed the subwoofer issue, but as far as the tweeters, that whine is still there.

At the time we were hooking up the sub, we never removed our amp grounds. The only wires dangling around were those from the tweeters..

So at this point, the whine still wont go away. Could it be a problem with the head unit up front? The grounds for the amps are solid.. and the whine for the tweeters only occurs when the engine is running. Thanks Kirk.

KRock459

Take a small guage wire, connect one end to the highs amplifier ground, the other end to the outer shield of the RCA input to the amplifier, see if that will fix it. It is common for audio systems to have "ground loops", basically the head unit ground has a different impedance to ground than the amplifiers have.

The best solution is to run a ground wire from where the amplifier is grounded and run it to the head unit, remove the factory ground at the deck and only use the new ground wire, its called reference grounding and ensures a more uniform impedance from head to amps.

Kirk R