Who knows the best way to wire my amp???


Okay.... I am a newbie so don't say too many bad things. I want to find out if I should wire up my 4 channel amp in a bridged or unbridged configuration.

I am powering 4 Rockford Fosgate 6.5" three-way speakers (FRC 4306) with a 400w amp. All 4 speakers will be the "front" speakers in my system. My "rear" speakers are allready wired and set the way I want off of another amp & the head unit.

The amp specs are as follows:

RMS @ 4 Ohm= 50w x4
Peak @ 4 Ohm= 75w x4
RMS Bridged @ 4 Ohm= 150w x2
Peak Bridged @ 4 Ohm= 200w x2

Can I bridge the amp and hook up 2 speakers to each brigged channel..... I assume then that each speaker could then get aproximately 75w RMS (instead of the 50w per channel that an unbridged set up would provide).

Is this a good/ bad idea?????
What would the pro's & con's be???

I just want to get some good volume out of the speakers.

Just let me know


Bubba those 3-way speakers u have hold 50 watts rms power and puttin 75 watts to them isnt a very smart Idea. 50 watts to each one is plenty if not too much usually u dont wanna exceed the highest Rms range a component speaker can hold where with subs u usually can exceed their power range.

OOOOOOOOPS ..... My bad for not looking at the speaker's RMS. I was thinking they were rated at 100w RMS, but that was the peak. Thanks for the quick reply though.

Bubba whats ur whole setup u said those are gonna be just ur front speakers?

I'll post it for ya tomorrow (cuz I gotta' get some sleep) with all the specs & locations... but the basic idea is:

Blaupunkt San Jose CD/MP3 Receiver..... 4 Rockford F 4.5" rear speaker as well as 2 MTX 6x9's...... Then the 4 front RF's...... 2 MTX amps.

I wasn't going to get any subs... but now I think I gotta have one, or two, or three :) Am still shopping for the sub(s) though because my wallet is getting a little bit thin on extra cash. I started with just wanting a better than factory stereo.... but seem to have gotten a bit carried away with myself.

Sorry so long to reply...

Here is what I have as far as setup in my poor old car, a 1994 SW1 Saturn wagon. A Saturn is the best I could do on a Paramedic's budget along with 5 kids.....Hell, the sound system is worth as much as the whole car..... anyway, here's the scoop:

Head unit is a Blaupunkt San Jose CD/MP3 Receiver. I also have a 20 gigabyte Archos Mp3 player attached to the Aux input of the unit.

My front sound is composed of the 4 Rockford Fosgate FRC 4306 speakers along with an MTX Thunder 6000 Series 4-Channel amp to power the 6.5" RF's (one in each door). The amp is connected to only the "front" output off of the head unit. All 4 Speakers were rewired & mounted in factory possitions with addition of foam baffels for protection. Rear doors originally had no speakers so I did have to do a bit of cutting to mount the speakers.

Rear sound is compose of 4 Rockford Fosgate HPC1205 5-1/4" speakers in the rear hatch. These are run straight off of the head unit and are mostly for "fill", using factory wiring, also with the foam baffels. In addition, I also have 2 6x9 MTX 6933 3-ways mounted in boxes. The MTX speakers are powered by an MTX 4202 2- channel amp. This amp is connected to the "rear" outputs of the head unit.

That is basically it. To me it is great compared to the factory system. Plus I got to learn a bit about car audio installation in the process. It may not seem like much of a setup to most, but at least I have to turn the volume down now to keep from going completely deaf :)

do not bridge the amplifier. bridged, the amp can only accept a 4 Ohm load, as in bridged mode, the amp sees half of the actual impedance. run the amp in 4 channel mode, and put one speaker on each channel.
that will be ideal.
if you need to get signal to all 4 channels, you can run one set of RCA lines, and use Y splitters at the amplifier to split from 2 to 4 channels.

contrary to popular belief, an amplifier doesn't produce more power when it's bridged. The maximum output is the same bridged at 4 Ohms, or stereo at 2 Ohms, and these are usually the minimum loads for an amplifier unless otherwise stated.
bridging is just there on a stereo amp to run one speaker (sub) with a stereo amp, or two speakers (stereo) with a 4 channel amp when the speakers are 4 Ohms.

my suggestion for that system overall would be as follows:
keep the four 6.5" RF speakers. run them with the four channel amplifier as front/rear and lose the 5" drivers inb ack. a speaker in each of the four doors should be plenty. Perhaps even sell all four 5", and the front 6.5" and put separates up front for better imaging and a brighter soundstage.
get rid of the 6x9" speakers and their boxes, and bridge that 2 channel amp that was driving them, and go with say, a single boxed 10" sub. It'll take about the same amount of space, and overall, your sound quality will improve tenfold with little money out of pocket.
also be sure you've used the proper amp wiring kit to get current to those two amplifiers. Doing this, you won't need the Blaupunkt's internal power any longer, as the 6 amplifier channels will handle everything.
you may want to use a 3 way electronic crossover like a Coustic XM-3 if that head unit has no subwoofer pre-outs though

Hey.... thanks for the advice.... I will do some thinking and tweaking. Then, let you know how it all works out. You gave me sme good ideas that are definately worth a shot.
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