Hello all,
I am new to this forum and happy to find so many BMW enthusiasts!
My name is Mario Pankov, I am from Bulgaria, EU ( as could be seen from my profile ) and I own a 97 E39 fitted with the m52b20 engine ( aluminum block ).
I got my car stereo stollen just a few weeks ago and now I got back to my original head unit. I was looking for this back conversion for a long time as I did not like the way my dashboard looks with an aftermarket cd player and I prefer to keep the car in its stock look.
The problem is the performance of the BMW`s factory sound system. I did replace the front door speakers with a 2-way Focal Polyglass 130 V2 component system, I added an 8" B&W subwoofer ( made for home use, but I was looking for a high SQ sound system ) and two Audison LRx2.80 amplifiers in my trunk, one for the front speakers and one bridget for the B&W woofer. The interconnects came from Audison as well. The big problem is the stock head unit - it really makes all these expensive components useless.
What I would like to do is to remove the stock power amp and cassette player mechanism and to get RCA leads out of the stock preamp. Then I will connect my power amps directly to the original preamp of the car.
Has anyone done that, if yes what are the results in SQ and does the stock preamp kill the sound ( in this case I would need to completely replace it with a good diy preamp

)?
Could anyone be able to provide the schematics of the preamp and amplifier sections of the Business RDS unit ( no external amplifier in the trunk version )?
If there are other people interested in such modification ( note it will also work on the X5 ), I will post my results.
The thread is more likely to be for the Sound forum, if true, i would ask you to excuse me and to move it to the correct place.