Need Help

horndog7 · #1 (**permalink**) 07-14-2007, 09:13 PM

I have an alpine head unit connected to e36 m3 factory amp which i also believe is alpine with HK speakers. I had it for some time, and i believe the stereo is self powered (may not be good). well the issue is that there isn't any sound, which at one point there was sound for a while and then it began to cut out here and there, thought it may have been a loose connection so i pulled out all the wires and resodered all of them. Right now there is and hasn't been any sound. Could it be the amp, radio ???? may i have an issue with both being powered???

carstereopro · #2 (**permalink**) 07-16-2007, 01:54 PM

Where in Mass are you, I can send you to one of my dealers to have them check it out for you.

It could be the remote turn on output of the radio, the factory amplifier (input or output stages failing), the factory head unit's output stage failing, a short, or something not quite as simple.

If you do not have the ability to troubleshoot it yourself, I'd recommend going to an experienced installer for help.

92SCHNITZER · #3 (**permalink**) 09-14-2007, 05:16 PM

You are outputting high-power out of your alpine headunit into the lowlevel input of the factory amp. It is only a matter of time if you listen loudly then you probably blew the input stage of the factory amplifier. This is a really easy fix just bypass it.

carstereopro · #4 (**permalink**) 09-16-2007, 02:52 PM

Quote:

Originally Posted by 92SCHNITZER

You are outputting high-power out of your alpine headunit into the lowlevel input of the factory amp. It is only a matter of time if you listen loudly then you probably blew the input stage of the factory amplifier. This is a really easy fix just bypass it.

Yes, there is a remote possibility.

But BMW's OEM Amplifier is designed to take a very high voltage pre-amp level input.

Installing an aftermarket radio through the pre-out section connected with the factory amplifier tends to limit the volume level that can be achieved. If an 8V aftermarket headunit were being used, this is not an issue (a waste if a nice headunit, but not a voltage issue).

The output voltage of the OEM headunit is somewhere between pre-out level and speaker level. As long as a fully clipped signal never gets sent to the stock OEM amp, he will likely never have an issue.

If he were to run the aftermarket headunit at full volume for prolonged periods, which would eventually damage both the OEM amp and headunit, he would likely blow the speakers as well. (not to mention the fact that above 3/4 volume the distortion, clipping, and popping would be unbearable)