# Help bridging a 4ch amp to two front channels for more power output



## movingzachb (Dec 13, 2013)

I haven't ever bridged an amp before. And I'd like to get more power to my front speakers. 

I have a 4 channel Eclipse 3422 (Bridgeable) amp. I am using two channels for the front speakers. 

It is a 50x4 Amp.

I'd like to bridge the channels for more power and have it sent to the two front speakers. I do not run a sub and I'd like to get stereo output from this amp into the two front speakers.

Do I need two of these (RCA input Y adapter) such as this:
Amazon.com: db Link CLY2FZ Triple Shielded RCA 2 Female To 1 Male Y-Adapter: Car Electronics to output the head units front two channels into all four of the inputs on the amp? Or should I be able to just use one set of leads to the amp in order to make it happen?

This amp has a switch that goes from 4/3/2. I'd assume I can set it on and accomplish this - given that I have it wired properly.

Would this diagram be accurate for what I want to do?









I'm running an Eclipse 8052 HU and a Ecipse 3422 4 Channel amp 50x4 with two Boston Acoustics Coax in the front.


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## turbo5upra (Oct 3, 2008)

looks about right- only question I have is if you have to feed both inputs- have a copy of the manual handy?


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## Victor_inox (Apr 27, 2012)

You don`t have to feed both inputs only 1 in each pair.


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## turbo5upra (Oct 3, 2008)

feed the left channel front and rear- labeled (mono) in the pics I found.... Mono, Stereo Or Bridged? Get The 411 On Amplifier Modes - Seismic Audio Speakers

I would feed right to left rear- and left to left front (shouldn't need y cables)

Then bridge the amp (it should show the screws to use on the side)

set the amp to 2 channel mode


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## movingzachb (Dec 13, 2013)

turbo5upra said:


> looks about right- only question I have is if you have to feed both inputs- have a copy of the manual handy?


That's the question I have. Do I feed two or all 4 inputs? No I don't have the manual I found one online for another Eclipse brand amp, but not sure it applies.


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## movingzachb (Dec 13, 2013)

turbo5upra said:


> feed the left channel front and rear- labeled (mono) in the pics I found.... Mono, Stereo Or Bridged? Get The 411 On Amplifier Modes - Seismic Audio Speakers
> 
> I would feed right to left rear- and left to left front (shouldn't need y cables)
> 
> ...


That sounds right. I don't think any of them actually say (mono) on them - but I'll give that a shot. Pretty sure I have the speaker connections on the right screws already.

Just googled and found this picture of the amp in question. Yes it does indeed say (mono).










Here is the other side.


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## movingzachb (Dec 13, 2013)

No luck. When I connect it up that way Left to Front (mono) and right to Rear on the amp and set it for 2 channel. I get only audio from the left front speaker. Changed it around every other way I could think of. I think this is because it may need to have an audio feed coming out of all four inputs to work as bridged. I can hear VERY faintly a bit of bleed audio coming out of the right speaker - but I think this is just that - bleed. I think it may need a normal signal to amplify from all the inputs - and maybe it does mean I need to use those Y adapters to run two sets of RCA cables to the amps inputs.


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## TrickyRicky (Apr 5, 2009)

When running mono, select "2ch" and ONLY USE the LEFT RCA input for both front and rear.


So there is no need for splitters.

Also am not sure since am not very familiar with this model, some/most amps when bridged they only are able to play a certain fhz range (low pass usually, under 500hz). Now am not saying this is true with yours or ALL amps. 

Try setting the amp to full range (if it has that option) and then the 2ch switch and use only left inputs for front and read. You should get signal out of both sides (front and rear when bridged). Also keep in mind that when bridging you cannot use a load lower than 4ohms.

Try it and report back...Good luck.


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## troutspinner (Nov 8, 2013)

FWIW, I have a rockford Fosgate amp and if I want to go to 2 channels, I have to split the input as shown in your illustration. I've tried it and it works, when not split, it is only half power.


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## UNFORGIVEN (Sep 25, 2010)

I bought OFC Y-Splitter 2 pack from walmart (a whopping 3$) and bridged the Front L+R and rear L+R

That worked for me on this amp.


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## theoldguy (Nov 17, 2009)

I had that exact same eclipse amp many years ago. I vaguely remember having to split the RCAs when bridging.


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## movingzachb (Dec 13, 2013)

troutspinner said:


> FWIW, I have a rockford Fosgate amp and if I want to go to 2 channels, I have to split the input as shown in your illustration. I've tried it and it works, when not split, it is only half power.


And when you do this -- it plays in stereo correct?

Because when I tried several combinations with just the one L+R input set and I could get either two speakers in mono or one speaker at a time. 
I was trying to deduct what was missing.


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## movingzachb (Dec 13, 2013)

theoldguy said:


> I had that exact same eclipse amp many years ago. I vaguely remember having to split the RCAs when bridging.


So you DID have to split them? 




> When running mono, select "2ch" and ONLY USE the LEFT RCA input for both front and rear.
> 
> 
> So there is no need for splitters.
> ...


I'll see. It has Just the High Pass, Low Pass, Through and the 4/3/2 switch only - I was starting to think that bridgeable meant to bridge with another amp. But it seems it should do both. I believe that when I had the inputs going to the Left (mono jack) and the one right below it - I got two speakers but in Mono not stereo.


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## TrickyRicky (Apr 5, 2009)

Its labeled right beside the RCA inputs...very clearly "MONO" input for rear and "MONO" input for front, which happen to be the LEFT inputs on this amplifier.

I clearly stated NOT ALL amplifiers do this, just most. The op's clearly states it only requires 1 input per side (front and rear) to be able to bridge those sections. Don't understand why its so difficult to try it.


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