Hi again,
I have an issue with a T600-4 in my car. The problem is that I get alternator whine in the front right speaker, the tweeter only when the heater or defroster is on. There is no whine in any of the other speakers. The front speakers are RF T1652-S Components, left and right. Ive swapped RCA inputs and the sound stays on the same channel. Ive swapped amps with a crossfire 4 channel and the noise is gone. Ive tried regrounding the amp and no change, It just started doing it about a month ago. Amp is not running bridged its rinning the components up front and 6X9's in rear. The amp is not under warranty. I have checked continuity on the RCA shields on the amp inputs and the all are connected. I dont know where to go from here. I dont wanna replace that amp, it really sounds great just when im not playing anything with the heater, fan or defroster on, I get whine through the front right speaker. Thanks for your help
I have an issue with a T600-4 in my car. The problem is that I get alternator whine in the front right speaker, the tweeter only when the heater or defroster is on. There is no whine in any of the other speakers. The front speakers are RF T1652-S Components, left and right. Ive swapped RCA inputs and the sound stays on the same channel. Ive swapped amps with a crossfire 4 channel and the noise is gone. Ive tried regrounding the amp and no change, It just started doing it about a month ago. Amp is not running bridged its rinning the components up front and 6X9's in rear. The amp is not under warranty. I have checked continuity on the RCA shields on the amp inputs and the all are connected. I dont know where to go from here. I dont wanna replace that amp, it really sounds great just when im not playing anything with the heater, fan or defroster on, I get whine through the front right speaker. Thanks for your help
Perry, Ive taken one of my old stock speakers and placed a long enough wire on it so I can listen to it while im inside of the car and so I can press the accelerator. I hooked the speaker up to the front right channel of the amplifier I ran the wire outside of the car and through the window. I started the car and turned on the air and the rear defrost, I was able to hear the alternator whine in that speaker really well, nothing in any of the other speakers. So yes the noise remains.
You'll almost certainly have to have the amp installed in the vehicle to troubleshoot it.
To troubleshoot it, you'll likely need something like the Radio Shack mini amplifier and test leads for it. This is generally better for troubleshooting strange, low level noises than a scope.
Before you do any troubleshooting in the amp, you should disconnect all but the test speaker from the amp and try both RCAs plugged into the noisy channel. It's very strange to have noise like this on only one channel.
If you can find absolutely no way to get rid of the noise, get the schematic from Rockford and send me a copy.
To troubleshoot it, you'll likely need something like the Radio Shack mini amplifier and test leads for it. This is generally better for troubleshooting strange, low level noises than a scope.
Before you do any troubleshooting in the amp, you should disconnect all but the test speaker from the amp and try both RCAs plugged into the noisy channel. It's very strange to have noise like this on only one channel.
If you can find absolutely no way to get rid of the noise, get the schematic from Rockford and send me a copy.
If the noise isn't caused by the speaker lead being next to the blower power wiring it will be caused by the rca shield for that channel being weak. I would assume it would be the passive crossover picking up noise through its inductors but you said you already ran the speaker wire outside the car so...
yes, I ran the speaker wire out of the car and to a different speaker, one that i can hold in my hand and i was able to hear it with the heater on, also the rear defroster causes it. Anyway before i went to work this morning I started my car up and opened the trunk and I pulled the RCA's off of the front channels and the whine got really loud, I put the right front RCA back on and there was no change in the noise, but when I put the left one back on it got quieter and the whine was back in the front right channel. Same thing with the rear channels but it didnt matter which one I had plugged in as long as the left or right was plugged in the noise was quiet. Didnt try it yet with none of the RCA's plugged in just did the front and then the rear as explained above. That amp is relatively newer I doubt fosgate will give me the schematics since it is an 09 model but who knows.
If the amp is still in production, they probably won't send you the schematic diagram.
Do you have another set of RCA cables that you can run from the head unit to the amp (over the seats/outside the vehicle)?
Earlier, it sounded like the problem was only in one channel, now it seems like there may be other problems.
Have you confirmed that your RCA shields on the head unit are intact?
Do you have another set of RCA cables that you can run from the head unit to the amp (over the seats/outside the vehicle)?
Earlier, it sounded like the problem was only in one channel, now it seems like there may be other problems.
Have you confirmed that your RCA shields on the head unit are intact?
yes, I do. Yes the shields are intact, Used the continuity check on my fluke, and there is continuity from RCA shields to headunit chassis. Even tried a different headunit. Same problem. I will try to run RCA cables outside of my car this weekend. I was hoping the amp was not the problem but im starting to think that it is though.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.