i got a pioneer Deh-1900mp with only a rear output.

i want to connect a 4 channel amp use front 2 channels 4 mids and highs and rear two for subs. can this be done even tho my headunit only has a rear channel?

 

Yes, a lot of 4 channel amps have a switch for 2 input or 4 input configuration. If you amp does not have this you can always use RCA "Y" cables to feed all 4 channels from the two outputs on your head unit.

 

yea i know that. but will the rear channel act as the frount will or will the sound be different

 

rear channel will most likely be for the rear. You could get an amp with hi level inputs and use it from the speaker wires on the harness and then amp the speakers and run the RCA's for your subs to the back

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by doggworld1233 &raquo;</TD></TR><TR><TD CLASS="quote">yea i know that. but will the rear channel act as the frount will or will the sound be different</TD></TR></TABLE> The output from the HU, [rear preamp output] will be stereo 2 channels and that's all that matters there, although you will not have fade control, at the amp either by switch or "Y" adapters, the front and rear channels will get exactly the same left and right signal, from then on things can change, first is input gain, that can be adjusted differently for the front left and right channels and the rear left and right channels, next is the active x-overs your amp should have, you have a choice of H/P, [high-pass] L/P, [low-pass] and off, the front ch. should be set on H/P or off, and the rear ch. set to L/P, on most amps you can also set the x-over point for both H/P and L/P both should be set at about 90Hz-100Hz to start, fine tune later.

Now to what I think your asking, if you connect both the front and rear speakers to just the front outputd of the amp will the front and rear speakers sound the same, is that correct?
If so no they will not, even if they are exactly the same speakers, the mounting locations are different, so they will sound different.

If the above was the way you where going to wire them, do this instead, connect amp to front speakers and the sub, connect HUs front speakers output to the rear speakers, You need very little power, [watts] for the rear speakers, [rear fill], It would also give you fade again, [although it's not needed] I would remove/disable any tweeters that are in the rear also. 94

 

The only affect in terms of sound if you run rear output to all 4 channels is that you loose the abillity to fade front/rear. Otherwise same stereo sound.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fcm &raquo;</TD></TR><TR><TD CLASS="quote"> connect amp to front speakers and the sub, connect HUs front speakers output to the rear speakers, You need very little power, [watts] for the rear speakers, [rear fill], It would also give you fade again, [although it's not needed] I would remove/disable any tweeters that are in the rear also. 94</TD></TR></TABLE>

Good suggestion