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Discussion Starter · #1 ·
Well I've decided to upgrade to a 4 channel amp. Here's what my setup is right now and what it's going to be when it warms up:

Currently:
Front: Factory component speakers
Rear: Factory 6x8
HU: Eclipse CD3200
Trunk: 250w RMS Phoenix Gold Octane R amp, 12" 250w RMS Phoenix Gold Octane R sub in sealed enclosure. Currently not working since I accidentally ripped the ground wire
Wiring: Monster cable 4 gauge kit

Planned:
Front: Boston Acoustic 5.25" Component speaker set w/1" tweeter
Rear: Boston Acoustic 6.5" Coaxial
HU: Eclipse CD3200
Trunk: Same sub/amp, but will re-connect the ground so it starts working again

Everyone tells me a 4 channel amp will sound way cleaner than the head unit. So I think I'm going to try it out. I found an amp, wondering if it's decent or if the price is good. It's a Rockford Fosgate 300X 4 channel amp. I'm after clarity, not volume.

http://www.usedregina.com/classified-ad/8460241

Person won't budge on the price.

My question is, what's your opinions on this amp, the price, and do I need to upgrade my wiring to get this to work? Or can I run both of my amps on the one 4 gauge kit?
 

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You can run both amps off your 4 ga wiring. Just add a distribution block to spit the power to the two amps.

That amp will definitely sound better than running the speakers directly off the HU. For $80, it's not bad. I'm not sure what Boston's you are choosing, but depending on their efficiency and power handling, I'm sure the optimum setup would be to give them more power than the ~ 40 WRMS of the RF amp.
 

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What I would do is forget the speakers in the rear doors or run them off the HU. Then bridge the RF amp to power the front comps. That will give you plenty of power.

Do you already have the 5.25" Bostons? If not, I'd get 6.5s instead.
 

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Discussion Starter · #4 ·
Using the same wires is a huge bonus for me.

I would have to check when I get home which Boston Acoustics I have. I bought them like 3 years ago. If I remember correctly they weren't very high wattage speakers when I got them. I want to say 100w peak for the components and 60w peak for the coax, but like I said I'll have to get those numbers when I get home.

Everyone keeps telling me I should amp the front and forget about the rears but to me it just seems like that would throw off the balance of the sound, hence why I'm looking for a 4 channel amp. I think I'll try it both ways.

Is that amp decent though? I know Rockford is very middle of the road for sound quality and I've always associated them as being the brand for kids that want loud subs, not clear subs. Keep in mind on the price that I'm in Canada, and a small town to be exact. If $80 is an okay price in USD then it's probably a good price in CAD.
 

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[quote author=speeedbump link=topic=139382.msg3004236#msg3004236 date=1237476915]
What I would do is forget the speakers in the rear doors or run them off the HU. Then bridge the RF amp to power the front comps. That will give you plenty of power.


[/quote]

I second this, bridging the amp will make a big difference in terms of power and midbass output. Keep in mind that some amps sound better bridged than others though.

Ahh didn't realize you already owned the speakers...

the amp is a little light on power for a 4channel, but the price isn't too bad. I would spend a little time looking around just to compare that price to other 4ch amps. Or even a nice two channel amp. Having only your front speakers playing will actually give you much better imaging than all 4 - remember stereo is only recorded with 2 channels for 2 speakers.
 

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Discussion Starter · #6 ·
That being said what may not be a bad option then is buying a 1 channel amp for my sub. Re-locate my 2 channel PG and put that to my components. Since that's 125w/channel RMS... hmm.... the only problem is that I already bolted that directly to my sub box and I don't want holes in it.
 

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That's an option, but I don't see it necessarily being a better one, unless you think you can find a good mono sub amp for less than $80.

The RF will give you 150 WRMSx2 bridged to the comps, and you can keep your sub set up the way it is, assuming you are happy with it now.

Either way, 125-150 w is more than enough for 5.25" comps.
 

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Discussion Starter · #8 ·
Wouldn't the RF be 75Wx2RMS?

I personally like the idea of leaving the sub the way it is. I'm very happy with it. I've had it like that for the last 2 cars (I guess 7 years now... wow is that a long time)
 

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According to the specs on your link and other online sources, it is rated at

37.5 watts RMS x 4 at 4 ohms
75 watts RMS x 4 at 2 ohms
150 watts RMS x 2 at 4 ohms in bridged mode

I assume your Bostons are 4 ohm. If you're just powering your front comps, you would operate it in 2-channel bridged mode, which gives you a rated power of 150 WRMS x 2.
 

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Discussion Starter · #10 ·
That is a really bizarre amp then. Well hey for 150wRMSx2 that's beautiful. The model number of the components is S50 and the coaxials are S65 btw.
 

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You'll want to go easy on the gain on the amp, lest you toast your speakers.

Or, since your Bostons are relatively efficient and have a relatively low RMS rating (55w for the comps and 35w for the coax), and if you think you prefer the sound of using all four speakers, I think you'd have plenty of power to drive all four with the RF amp in 4-ch mode.

If you feel like upgrading the front comps down the road, then you could reconfigure as suggested above (amp the fronts, HU to the rear).
 

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Discussion Starter · #12 ·
Well and honestly too, I was really happy with the way they sounded running off the HU in my old car. Still sounded really good.

But if that's the case I'll go pick up the amp tomorrow. Can't go wrong for $80. Now all I need is a case of beer and a warm day.
 
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