Help - What's Preamp out?

[cregr]

I'm looking to buy a mp3 head unit. I have an amplifier (no EQ) and a 1o Cd changer. I'm not very familiar with car audio terms. How do I hook up a head unit to a amplifier (not the actual wiring but what do I need in a head unit)? How many pre-amp outs do I need? Etc. etc. etc....

Thanks

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[cifer721 10+ year member]

well, all you need to look for is a head unit that has one pair of rca's for each amp that you get. for example, if you are looking to power ur front speakers with an amp, then u need one pair of rca outs from ur HU. some of the newer HU's have three sets of rca's. one for the front set of speakers, one for the rear, and one for subs.

 

[Savant 10+ year member]

One set of RCAs can feed 2 amps (or more I'd immagine, but each time you split that signal you are gonna loose voltage to any given amp).. If the HU only has one set, I'd immagine you can't do any 'fading' adjustments on it.. When you have 2 sets, one is for front and one for back.. you can 'fade' between them (maybe, otherwise I see no point in one being front and one back, they would both be the same).. Some have 3, one front, one back, and one that's designed for just subs..

So, depending on what you think you need for amps, you can probably get away with just 1 set of pre-amp outs.. If you are just gonna run subs, 1 set is fine...

 

[cregr]

Thanks for the replies,

My amp has 2 RCA's in (for front and rear). I assume I should get a head unit with 2 RCA's out and hook it straight in? Should the head unit have an equalizer? and should it be the same brand as the amp?

C

 

[Savant 10+ year member]

Originally posted by cregr Thanks for the replies,

My amp has 2 RCA's in (for front and rear). I assume I should get a head unit with 2 RCA's out and hook it straight in? Should the head unit have an equalizer? and should it be the same brand as the amp?

C

Brand is irrelivant (as far as matching amp/hu).. I take it you have a 4 channel amp then? You only really need to have 2 (sets of) pre-amp outs if you want to seperate your speakers to be front/rear.. that is, if you are gonna run just some subs from the 4 channel (bridged for 2 subs maybe?) then you only need one set of pre-amp outs.. split the signal into both channels of the amp.. If you have 2 sets, changing the fader would change one of the subs, but not both.. better to keep both subs the same (again, presuming bridgin 4 chnl to 2 subs).. If you want sub(s) on rear and some other speakers on front, then 2 sets would be better..

Just all depends on how you are gonna set it up..