1 Amp or 2 ?

TROOPER

That's what I was thinking, but just looking for opinions before I pull the trigger.

I heard the Alpine PDX-5 is good, but not convinced 300w is really a lot to drive a 12" subwoofer.

As I could get 2 Rockford amps for the same price as the Alipne, as per my original post.

But opinions vary on the quality of the Rockford amps.

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Darren
"Guv Motors Passion Wagon"

pg6speed

Trooper,
This is the first car that I've run a single amp in and I have to say I am very happy with it. I opted for the Polk Audio PA1100.5 80wx4 @4ohms and 600wx1 @1ohm. Its a very big amp but no larger than 2 amps side by side and has twice the sub power as the Alpine for a few hundred buck cheaper. Another option is the Kicker 08ZX550.3 70wx2 @4ohms and 420wX1 @2ohms if all your running is 1 pair of speakers and subs this is a good option at a great price.

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STILLEN G3 / F.I. TDX (NO RESONATORS) / F.I. LTH / UpRev Tuned / BC-Racing ER Coilovers / DIY Oil Cooler / Short Shifter

Zuppy51

Checked the sub specs you want to use at 2 ohm load for optimum watts. ( Rockford says: Power Handling 500 Watts RMS
1000 Watts Max)

I have a PDX 5 in my truck. It's driving a JL 12" Wedge box @ 2 ohms. JL Specs the optimum for my driver at 300w at 4 ohms or 600w at 2 ohms.

The PDX came with a bench test birth certificate, it reads 414w for the sub, and 114 for the fronts at 4 ohms. (Double the sub at a 2ohm load to 828w!

Edit: The Ohm rating is the resistance offered by the Sub. Most amplifiers are stable at 2 Ohms, and all are stable at 4. However, most amps are able to put out (roughly) double the power at 2 ohms, because there is "half" the resistance.

If you're going single sub, I recommend going with a 2 Ohm sub (or if it's dual voice coils, 4 ohms).

If you're going with two, I'd go with the 4 ohm (or if it's dual voice coil, 2ohms). The reason for this is because of how you wire them.
(There are 1 ohm stable amps out there, but they're typically only found in higher end amps).

I just used simple ohm's law to come up with that double output rating at 2 ohms. I would have to test it to be sure. But the math is pretty simple.

I have mine bridged for the fronts. Which make it 228w for r/l and sub mono at a 2 ohm load of 828 w for the sub...

It hits hard and clean, no noise, no issues at all. Very stable, never runs hot.

This is a killer little amp. I'm loving it, and you can hide it very easily.

I have a JL 900/5 in my 370z now, and I kind of regret spending the extra money. I cannot see the benefit.

BTW you can get the Alpine for 350 off the net with a warranty. I spent 3x on the JL 900/5, I'm regretting it big time.

TROOPER

I understand these come with tested "birth certificate" numbers, which from what I've seen tend to be higher than actually rated.

But I didn't see any specs stating this can drive double the output rating at 2 ohms (800w+)

The PDX-5 is rated stable for 300w @ 4 ohms, right?

__________________
Darren
"Guv Motors Passion Wagon"