Need help picking an amp

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Shaggy
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Need help picking an amp

Post by Shaggy »

So i am going to be buying a 12" rockford fosgate punch p3d412. Its peak watt is 1000 and its rms is 500. I kind of have a clue about the ratings and stuff from looking it up on the internet but i need some guru input. I want to keep it at a low cost and i was wondering what amp i should get to power this sub. I was checking the Sony 2/1-Channel Xplod XM-GTX1852 and its peak watt is 1000. Would this be a good enough amp? I dont need the best or most expensive amp, im not trying win some competition, i just want it to sound good and make the pussy's vibrate.
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Legacy777
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Re: Need help picking an amp

Post by Legacy777 »

When looking at amps, disregard the peak power, you need to look at RMS power. Lower power amps can power a larger sub, but typically you end up having to drive the amp pretty hard and it's easier to get distortion.

What is the RMS power on that Sony you mentioned? If it's around 500, you should be good. You can go higher, and just have a lower gain setting, which typically improves sound quality and turn down.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
Shaggy
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Joined: Fri Apr 16, 2010 8:49 pm
Location: Grants Pass, Oregon

Re: Need help picking an amp

Post by Shaggy »

200W x 2 RMS at 2 ohms with a max of 500, but since its a two channel and ill bridge it and it will be 400 x 1 rms at 4 ohms with a max of 1000. It says its a 1000 watts right on the amp, but when u look at the details it say it can be used as a bridging amp and it will have the max power at 1000.

The sub is a dvc sub too. Will i be able to hook it up right? Or will i just have to run off of both of the channels . Will that be the same as hooking it up bridged?
Last edited by Shaggy on Sat Jun 11, 2011 6:48 am, edited 1 time in total.
90 2.2 N/A legacy awd wagon with outback struts.
subydaddy
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Re: Need help picking an amp

Post by subydaddy »

I have an old digital 1000W amp I'll sell ya. I'll have to check the brand and what not but it's a good amp. Won't over heat either.

PM if interested, we can talk price.
subydaddy
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Re: Need help picking an amp

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Legacy777
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Re: Need help picking an amp

Post by Legacy777 »

You will need to run both voice coils on the subwoofer, and because they're 4 ohm voice coils you will most likely need to run the wiring in series. Here are some pictures from Fosgate's site on the different wiring setups for a single woofer and the resultant load the amp sees.

Series Wiring
Image

Parallel Wiring
Image


The problem with the parallel wiring is that when you bridge an amp it cuts the speaker load in half. With the parallel wiring setup, that would give you a 1 ohm load, and most amps are not rated down that low and would likely overheat. You'll find some high end competition amps rated at 1 or 1/2 an ohm. But they're big bucks and for the crazy competition guys.


So, for your setup if you used that amp and the sub, the amp would be putting out the 400 W RMS at 4 ohms.

I found this document while searching for some diagrams and it's a good overview.

http://www.outrageousaudio.com/page_fil ... g_subs.pdf
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
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