I have asked several times if the outputs from the BOSE HU (head unit) are speaker level (i.e. higher current) or line level and have received several answers stating yes and no using several different terms.

I want to get to the bottom of this.

G35 factory manual shows stock HU wired directly to speakers and the BOSE HU wired to the BOSE amp in the trunk, then to speakers.

There are several possibilities.

1) Stock and BOSE HU are identical except for minor features, etc and output a "speaker level" signal. In stock it goes to speakers, in BOSE it goes to amp, where is most likely signals across a high load, either in a single ended or differential configuration.

2) Stock HU outputs "speaker level" to speakers and Bose HU outputs a line level to BOSE amp in a single ended or differential.

Has anyone hooked up a multimeter to each positive and negative of a BOSE HU output channel?

With a test cd and a sine wave track the positive and negative should have the same abs. value but with different signs when the multimeter is in AC mode with respect to ground if it is a differential signal.

One of the wires will be approx, 0V if single ended.

Hook a brother up in any way if you can!

 

bump

 

I dont know the direct answer except you can not plug in directly to an amp. You have to use a hi/lo converter or line out converter if that helps. Therefore the signal from the HU to the amp is not clean as if you were using a radio with a 5 volt output. However the converter is not so bad as if you were to buy a cheap headunit with a 2 or 3v out.

 

Although the service manual is not entirely clear based on my quick read, everything else I have read indicates speaker level outputs (+ and GND) from the HU, which either goes directly to the speakers in the base system or to the amp in the Bose system. For this reason, line level converters are required if you wish to swap out the amp and use line level inputs. Now if your amp has speaker level inputs (and 6 channels), then you are good to go.

<P ID="edit"><FONT class="small"><EM>Edited by rcdash on 11/03/04 05:50 PM.</EM></FONT></P>

 

I dont know the exact answer to this question, I asked the same one a while back but no one could answer it then either. I am of the opinion that the two decks are in fact the same.... the bose amp acts as an eq for the door speakers and is an amp for just the sub.

"Dont start none, Wont be none"