Changed Amp (PPI --> Polk Audio)

[Hicompression]

Well...I was using an old skool PPI A300 amp in bridged mono mode (300 watts at 4 ohms) to power an Alpine 12" sub mounted in a ******** corner box. The problem with the PPI amp is that it was a class A/B amp and did not have an internal crossover. I was also getting a nasty pop out of the sub when I would open the car door and the head unit would completely turn off. In addition, I was using a PAC remote knob wired between the outputs of the ******** harness and the inputs of the amp to control the bass (which I didn't care for). The PPI is a great amp but would be better suited driving mids and tweets.

So...I did some research and ended up purchasing a Polk Audio PA600.1 amp. It's a Class D, Monoblock amp and also runs 300 watts at 4 ohms (the Alpine sub I'm running has dual voice coils wired in series at 2 ohms + 2 ohms). It also has a telephone plug jack built-in for a Polk Audio remote bass knob (included with the amp).

After installation I hit a snag. I had a problem with the amp going into protect mode with the ******** harness connected. At first I wired in a Scosche LOC which got the amp working but even with the gain on the LOC and amp all the way up, I was getting waaaaay too much signal attenuation. So then after talking to Steve@******** and some other knowledgeable people on this site, I tried wiring a PAC SNI-1 ground loop isolator into the rear left and right RCA's coming off the ******** harness. It solved the problem. The Polk amp doesn't like the DC current that is carried in the factory wiring.

So after wiring in the GLI, All I can say is WOW! I'm getting more bass than I ever got with the PPI amp. I'm very pleased with the PA600.1. It's a very well built heavy and large amp (~14 lbs).

So here's a before and an after pic. The PPI amp was definitely prettier...but at the same wattage, the Polk Audio amp outperforms it hands down. It's not even a contest.

[Topdown]

mmm art series... great amps!

[Hicompression]

Originally Posted by Topdown

mmm art series... great amps!

True. But nothing beats a dedicated monoblock amp like the Polk Audio PA600.1 that I replaced the PPI with.

[skuttduck]

Originally Posted by Topdown

mmm art series... great amps!

I still have my old art series installed in my Camry. They are holding up well and sound great.

[Sawyer]

Originally Posted by Topdown

mmm art series... great amps!

[oachalon]

i loved my old art series PPI amp.

Unfortunately i sold it with my old Lanzar Opti amplifier (this is when lanzar was one of the best and built by steve mantz). Two solid amps.

Both are still going strong today to the person i sold them to.

[Topdown]

Originally Posted by oachalon

Unfortunately i sold it with my old Lanzar Opti amplifier (this is when lanzar was one of the best and built by steve mantz). Two solid amps.

Love me some Zed amps...

[2010SLVRBULIT]

Polk more efficient..

[Hicompression]

Originally Posted by 2010SLVRBULIT

Polk more efficient..

Absolutely. You can really hear and feel the improvement. A Class A/B amp (PPI) vs. a dedicated Class D monoblock amp (Polk)? It's no competition...

[Topdown]

and your electrical system thanks you for the switch as well! heheh

[Hicompression]

Originally Posted by Topdown

and your electrical system thanks you for the switch as well! heheh

Maybe that's why my headlights would dim when the bass would hit while I was idling at a stop with the PPI. The Polk amp doesn't do that and it hits harder than the PPI did.

[Topdown]

Originally Posted by Hicompression

Maybe that's why my headlights would dim when the bass would hit while I was idling at a stop with the PPI. The Polk amp doesn't do that and it hits harder than the PPI did.

Class-D amps draw less current than Class A/B amps...

Also, a lot of Monoblock sub amps have a built-in bass boost to them, even if/when the adjustable boost is set to 0, the audio path is boosted, that may partially explain why it hits harder now. Additionally, the caps inside those old school amps need to be replaced as they lose capacitance over time, which would also partially explain why the new amp would hit harder.

Either way - I have always liked the look of those Polk amps, glad to hear that it was a good upgrade for you!