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Discussion Starter #1
Howdy Dudes,

I’m going to wire up my car for a sub in the trunk.

I already have a 12 inch Alpine “e-type”, from like 2006. It wasn’t so great in my last car, but I’m not sure if that could be due to not having enough power, and/or a junky amplifier.

This time around, I was going to go with a nicer JL sub with an Alpine amp. BUT I was thinking about trying my old sub with the new, better quality, more powerful amp, first.

Here’s the deal though: The old "e-type" sub is only rated at 250 watts RMS, and the new amp I’d be getting outputs 500+ watts RMS (won’t know actual output until I get the amp, since there will be a test sheet with it). It could even bench at more than 600 watts RMS.

Anyway, does this have bad idea written all over it? Will I smoke the old “e-type” sub almost immediately? Should I not even try it?

Also, for running 500-600 watts RMS, should I use a 4 gauge power wire?

Thanks all,

-Nathan
 

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The 500 watts on the amp is the maximum output for the amp. You'd have to look at the specs of the amp, it may only do 500 watts bridged, if it has 2 channels. Which means, each channel probably does 250 watts. So, you could just connect it to one channel, instead of bridged. Otherwise, you could connect the sub, but keep the output on the amp down below half volume. I think there'd still be a risk of blowing the sub if you turn the volume up too loud though.

At 500 watts, you should be good with an 8 gauge wire.
 

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Discussion Starter #3
The 500 watts on the amp is the maximum output for the amp. You'd have to look at the specs of the amp, it may only do 500 watts bridged, if it has 2 channels. Which means, each channel probably does 250 watts. So, you could just connect it to one channel, instead of bridged. Otherwise, you could connect the sub, but keep the output on the amp down below half volume. I think there'd still be a risk of blowing the sub if you turn the volume up too loud though.

At 500 watts, you should be good with an 8 gauge wire.
Thanks man.

I was going to go with this amp -- :


I was a bit off on the wattage. Looks like it is 650 watts at 2 ohm and 450 watts at 4 ohm. My guess is that it is going to be over 500 watts RMS @ 4 ohm in reality though. When I was at the stereo store we pulled some out of the box and the official bench test was significantly more than they were rated at.

If I hook this up to the sub and it smokes the sub, will it hurt the amp?
 

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If it's a mono amp, I think you safest bet would be to look for a new sub as well. With 650 watts, you'd have to turn the output on the amp waaaaaayyy down to keep from blowing the sub. At that volume, I'm not sure you'd get the bass that you're looking for.
 

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It's always good to have more power than you need. I have put 2-3 times more power to a speaker than it was rated for. There is many other things that come into play. Good trusted brands tend to be closer to real specs. But setup, and program material has a lot to do with it.
 

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Rule of thumb is to match your amps RMS out put to the RMS rating of the sub, but a little more power wont hurt it. Check the ohm rating of the sub and the rating for the amp at that ohm setting. If you blow the sub and keep playing it, it could damage the amp but not very likely. Another thing to keep in mind, distortion is the No.#1 killer of any speaker. I would personally run 4 guage wire for that amount of current draw, better safe than sorry cause if you over heat inferior wire you could catch your car on fire.
 

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Discussion Starter #7
Thanks guys.

As much work as the install is going to be, I might splurge right off the bat and go with a completely new sub, rather than try to make the old one work. It's tempting to save a money though and I guess I don't have too much to lose by trying the old sub, except all the time I'd spend trying to tune it, which could actually add up to be quite a bit.

If I go with the new sub, here is the one I'm thinking: JL Audio CS112RG-W3v3 Sealed PowerWedge™ enclosure with one 12" W3v3 subwoofer at Crutchfield.com

It's rated up to 500 watts RMS, at 2 ohm.

The amp is advertised at 650 watts RMS at 2ohm, although I think it will bench significantly higher than that.

Would that be OK?

If that is too much, any other suggestions, amp wise?
 

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I think that amp and that new sub will work pretty well together. The output matches, so that's probably the best way to go.
 

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500W RMS amp on a 250W RMS sub is fine, just be sure to not set the gain too high on the amp, be careful for distortion / clipping.
 
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