# New Stereo Install



## Sam (May 12, 2003)

I decided to change the factory radio with a Clarion DXZ735MP MP3 player (since the color matches interior lights) in my 92 525i and the technician at Crutchfield mentioned that I need an adapter that wires up between the headunit and the factory amplifier. 

He said I needed a power match adapter for converting floating ground and common ground. I had not read about this anywhere on the forums so I am unsure.

Is this adapter really required? What happens if I dont install it?

Thanks
Sam


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## jvr826 (Apr 22, 2002)

Sam said:


> I decided to change the factory radio with a Clarion DXZ735MP MP3 player (since the color matches interior lights) in my 92 525i and the technician at Crutchfield mentioned that I need an adapter that wires up between the headunit and the factory amplifier.
> 
> He said I needed a power match adapter for converting floating ground and common ground. I had not read about this anywhere on the forums so I am unsure.
> 
> ...


I installed a Blaupunkt head unit in a 1994 540i without any Line Output Converter (LOC) . If I remember correctly, the new head unit powered the speakers, but that was a long time ago and I could be mistaken. In either case, we did nothing special to connect the new head unit from Crutchfield. The harness they provided wired right in and we were done quickly.

So you want to use your new head unit to send signals to the factory amplifier... I did the opposite in my 2002 530 and I used a LOC between the factory "stereo" and the aftermarket amplifier. This device handles the ground matching and is adjustable to allow for tuning the input signal to the amp.

It seems you can use the same type of device to match your new head unit with the factory amp. I'm not familiar with the system in the '92 E34, are the speakers crossed over internally to the amplifier as in the E39? If not, why not just power the speakers with your new head unit directly?

If you need an LOC and you don't use it, you will get an incredible amount of alternator noise in your system, and/or, your factory amp will not produce any sound. In my '02, without the LOC, my amp would turn off instantly when the RCA inputs were connected. The odd thing is, in my '99, same car, same amp (part numbers confirmed) I did not need an LOC. I was able to connect the factory system directly to the aftermaket amplifier, no noise, no problems. This stumped me, but I broke down and spent the $100 on the LOC for the '02.


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