I'm hooking up an Alpine 9855 head unit to a Soundstream XTA480.4 amp. I currently have Infinity Kappa Perfect speakers and an 8" JL Audio sub.

I had several questions and I'm hoping the audio gurus can help me out:


1) The Alpine says it outputs 4V from the RCA connectors. The amp has a line level adjustment, currently set from the factory at the minimum setting. The amp documentation says that the line level adjustment goes from 500mV to 4V. I'm assuming that right now it's set at 500mV since it is at the lowest setting. Should I turn it to max, assuming this sets it to 4V?

2) Both the head unit and the amp have crossovers built in. Would it be better to use the subwoofer-out on the head unit and set the amp to full range (using the crossover in the head unit), or should I use one of the "normal" RCA-outs on the head unit and set the crossover on the amp?


Thanks for any help!

 

bump

 

I could be wrong...but I can offer some insight. I have a alpine as well and it has 3 preouts. Front, rear, and sub. I also hav the same type of Soundstream amp, but mine's is 360.4 instead. I don't have a sub though.

If I were you. I'd have 2 sets of RCAs going into the amp. 1 set for the fronts and 1 set for the sub. That way, you can control the volume of the fronts and sub seperately throught the deck. Now, into the amp, I know the amp has a bunch of settings, for 2 channel, 3, and 4. Set yours to 4 channel for driver's side, passenger's side and sub (2 channels). Bridge the sub and set it to LPF to only let the lows in. Your fronts should be full.

Then just tune it. Ask others for tunning, I don't know that much myself.

 

1) Set the line level input to whatever the output is on your HU. You are really supposed to turn the volume on the HU up to as loud as you would ever listen to it. Then turn the input knob up until you begin to hear distortion. Then dial it back again (it is usually around the output level of the HU). Do the same with the sub gain. See the FAQ for tuning an amp.

2) Use the Subwoofer output on the HU to run signal to the sub. That way you can use the internal crossover in the HU to control the frequencies (I am assuming the 9855 has a true crossover and not just a Q control and center control). If you ran RCA's from the other "normal" outputs to the sub, the sub would be seeing the full range of frequencies that the door speakers see (which you do not want). Once again...check the FAQ on wiring an amp.

John