Ok, so I had the setup installed at a local shop, they do really nice work. They did a nice clean install, with a high to line level converter, I think they ran it off the stock bose amp. So he hooks it all up, and it still sounds like the stock system. The driver is moving air, and the amp is on and making a definite signal...so he plugs in a tool called a tone tester or something? The damn sub shook my whole car...Turns out the signal going into the amp isn't a high enough voltage? What did they do wrong? I'm bringing it back tomorrow for them to futz around with. It's a phoenix gold zx400ti driving an eclipse 881000 aluminum dvc...The mentioned putting in a line driver to boost the signal, that doesn't seem necessary, what gives?

i also originally tried the line level converter method off the rear speakers, i really thought it sounded like **** so i decided to use the outputs on the back of the symphony and run rca's to the amp- it sounds good.

Use the line level outs at the head and run RCA's to the back. This will sound much better. BTW the head puts out about 1.5 volts which should be plenty to drive an amp, any amp.

Hey man, quick question.

How are u running the RCA'S from the back of ur headunit to the amp? Are there open pre-outs at the back of the Symphony unit? My installer was saying he had to use a line level converter and tap into the rear speakers or something, but I'd like to get the cleanest signal/power possible.

Thanks for the info man, If you could leave me some detailed info to take into the installer, I would greatly appreciate it.