(hopefully someone can answer before my installer calls back)

First: AUX Input Voltage Specs

I am having him wire an existing factory CD player into my empeg, and he just called and said that the CD player line-out is probably under-spec, since he needs to crank the empeg volume way up to hear it at all.

What voltage is the empeg expecting on the AUX line? 1V like what the empeg puts out itself, or less? Installer tells me 0.5V is average/standard. He can throw a line-amp in there to bump up the signal, he says, but I'd rather not have to.


Second: Headlamp Sensor Line

What voltage is the empeg expecting on this line to indicate that the car's headlamps are on? Maybe its my dimmer settings on the empeg, but he says it seems to behave opposite of what he expects. Says it goes bright with headlamps off, goes dimmer with headlamps on. I would expect that the empeg looks for +5V on that line to indicate headlamps are ON, yes?


Third: Common Ground

Also, he says that the empeg, on its own, in the car, does not have any ground-loop noise, but when he adds my factory unit back into the equation, there is ground-loop noise. Is there any way of grounding the CD player some other way? I am wondering if "ground-loop noise" is the magical term stereo shops use, sometimes justifiably, to get more $$$ out of the install.

- - - - - - - - - - - - - - - - - --
MK2 #141, green, 12GB