Re: 147-Blaupunkt pre-out into Bose amplifier
OK, finally did the pre-out mod, by removing the amplifier IC as well. So now my HU has 4 channel pre-out conected to the "speaker out" harness on the HU.
When connected to the Bose, volume need to be cranked up to 60 or more for decent sound level. Therefore, there is a attenuation circuit in the Bose. And there's also audible little buzzz noise (what's the possible cause?) when the engine is running.
However, intitial listening result is that the sound quality is much much better with the pre-out, definition is like "10 times better", highs' resolution are better, better transient, bass is not "boom-boom" but tightly controlled. Vocal is warmer and more real. There's no background noise when engine is off.
Meanwhile, will try to figure out how to eliminate the buzz & the attenuation circuit in the Bose, failing which, will start looking for another amp.....
note for picture:- there are other connections on the other side of the PCB too....
Last edited by colins; 01-01-05 at 13:44.