Hooking up Alpine amp for sub. Help, please.

[AJ_'04 Vibe]

I've done a few searches and have found quite a bit of info that helps a lot. Thanks to those who posted things like wiring diagrams, sub suggestions, etc.Anywho, I have a 4 channel Alpine amp that I want to add to my system and run a bandpass sub box with it. The Alpine has speaker level (high level) inputs that I want to use, but I'm not sure if I should jump into the factory wiring before or after the factory amp.I do know I want to hook up the amp to the rear speakers wires, that way I can sorta control the "volume" of the subs with the fader on the factory HU. I would think I should use the wires coming from the factory amp, but I don't want to overload the Alpine amp with too much input voltage.What have some of you done???Another idea I had was using the wires that go into the factory amp, and attach RCA (aka phono plug) connectors to hook to my Alpine amp. The Alpine already has an internal x-over, so that's not a problem. The only problem with doing that would be knowing the output voltage of the factory HU into the factory amp.Thanks for any and all help.

[Jahntassa]

You'd want to go after the amp. The hi-level inputs are designed to take the higher speaker voltage. It might not matter which you take, but I would think after the amp would give a stronger, cleaner signal overall.Your second idea would NOT work. Putting a hi-level source into your RCA inputs would potentially destroy the inputs on the amplifier. You'd need a line-level converter in order to do that method. The line level converter would take the speaker-level in, and give you a pair of RCAs. That's usually the preferred method for hooking up an aftermarket amp to a stock stereo.That kinda help? If not, ask away! We're here to help!

[AJ_'04 Vibe]

Cool. Thanks.As far as the RCA plugs, I meant jump into the wires before the amp. To me it would make sense that since there's a factory amp that the factory head unit would have low level output to the amp. Maybe not. That would make too much sense and make life too easy. Heaven forbid that happen. Thanks again.AJ

[Jahntassa]

Quote, originally posted by AJ_'04 Vibe »Maybe not. That would make too much sense and make life too easy. Heaven forbid that happen. Exactly...