Tech question (soon to be the last ;-)

[Waterwookiee]

OK, I know I have been dominating this board for a week or so, but I am close to finishing up my system, and I will have pics for everyone soon. Thanks for all of your patience and help. It's a good group in here....

I do have a couple of tech questions however.

For now, i think I may still try to keep my stock head unit for security reasons. Besides it's cool to have a stock looking truck that blows everyone away..

1) I am now running my speaker wires to my Alpine MRP240 through the speaker level input built into the amp. I want to bridge the amp into two channels and the only instruction in the manual shows the RCA inputs being used. Can this be done with the speaker level inputs as well? Or, should I just get a line level converter? Where should be converter be mounted (by amp, or by head unit?). Is there any quality difference between the converter built into the amp, and an outboard one? Any suggestions on a good quality one?

2) One of my other problems is that I get a lot of noise that seems reletive to the alternator in my truck. WHile the engine is running, if I turn off the stereo (but the amp is still on) I can her electical interfierence thourgh the speakers (it changes in pitch as a rev the engine). But if I turn the key to the "ACC" position, (thus the engine stops), the system get's quiet (amp is still on). So I have some interference somewhere (probalby the power cable?). What steps can I take to cure that problem? Are these inline noise killer any good? My power cable is pretty old and only eight guage (soon to be replaced), are there better cables that will help isolate the feed from interferance?

Thanks in advance.....

[WhiteRabbit]

1) I'd use the line level converter.

2) Sounds like you have alternator whine. Is your power cable running adjacent to any other wires? mainly RCA, speaker, etc.?

[cam2Xrunner]

Also try grounding your headunit's chassis...even the stock one.

[Waterwookiee]

No it's not. I have it running under the driver side kick panel and rocker panal. All of the speaker wires and other leads run under the passenger side. HMMMM

[JLTD]

1 If you amp accepts hi level inputs it's far better to use it than an LOC. Most LOC's use cheap transformers that have no business in audio. The less "stuff" in the signal path the better.

2 Noise is rarely caused buy ground issues yet its blamed first 100% of the time. Tracking down noise issues is a process of elimination and it usually the reult of the installation.