Planning a mobile sound system upgrade for my '03 G35 coupe

[shdowflare 10+ year member]

Okay guys, I have to switch gears for a second...

I was pretty set on getting a pair of JL Audio HD amps (750 and 600) to take care of my four main channels and the sub channel, however it turns out that I am able to get a great deal on the Polk PA1100.5...

That said, will it work for my requirements? As of now, I think I'm going to get two 4080 enclosures, and put JL 10w1v2-4 woofers in them. Would the Polk amp be able to power the four main channels (125x4@2ohms), in addition to two woofers on the sub channel? Seems like a lot for one amp to handle. Keep in mind those JL subs run 150w RMS each @ 4 ohms. I was thinking I could hook them up in parallel so they run at 2 ohms. The Polk amp runs 600x1@1ohm for the sub channel. Is this a good option to power my system? I will literally spend like $200 for my amplifier needs vs. about $1000 for those JL HD's. But I want to make sure it's gonna work!

As for physical fitting, based on some other G35 owners pics of the JL 500/5 mounted in the OEM Bose amp location I think the Polk amp would actually fit in there (though it'd be tight). It's six inches longer than the JL, but I think there's some room to extend a bit more if necessary, as noted from the pics I saw.

Thanks!

Brian

 

[FJF 10+ year member]

I will literally spend like $200 for my amplifier needs vs. about $1000 for those JL HD's. But I want to make sure it's gonna work!

Sounds like you found your amp.

 

[shdowflare 10+ year member]

The price is definitely right! But if I run with that Polk PA1100.5 I will have no additional room (in the "hidden" OEM amp location) to put another amp. So it's basically all or nothing.

Reliability is a huge factor for me. I know this is a sweet deal but if it's not going to sufficiently power my configuration then I'm not sure it's the right move.

This is what that single amp would be powering:

*Front doors: Infinity Kappa 60.9cs component speakers (w/ tweeter) (90w RMS/270w Max)

*Rear sides: Infinity Kappa 62.9i 6.5" speakers (75w RMS/ 255w Max)

*Rear deck: Infinity Kappa 692.9i 6"x9" 2-way speakers (110w RMS/330w Max)

*Trunk subs: Pair of JL Audio 1 0w1v2-410" woofers (150w RMS/300w Max)

I'm just wondering if running two amps would cause each to run with less load and thus less distortion, etc. vs. one running everything and getting pummeled (which could lead to sound, power, or other issues).

Some other things to consider, the PA1100.5 is rated at 125w x 4 @ 2ohms on the main channel, and 600w x 1 @ 1ohm on the sub channel. Is that too much power for the speakers above?

 

[FJF 10+ year member]

I'm just wondering if running two amps would cause each to run with less load and thus less distortion, etc. vs. one running everything and getting pummeled (which could lead to sound, power, or other issues).

That's not a reason for concern.

Some other things to consider, the PA1100.5 is rated at 125w x 4 @ 2ohms on the main channel, and 600w x 1 @ 1ohm on the sub channel. Is that too much power for the speakers above?

The speakers don't magically explode when the amp is rated for more power. You're the one who controls the volume. FWIW, my speakers are rated at 125w, as if it's relevant, and I'm feeding them with more than 400wps. Good luck.

 

[Plutoman 10+ year member]

Run the comps and 6x9's off the main channels, afaik, all the infinity speakers are two ohms. Plenty of power. The sides, I'd run off the head unit. If they and the 6x9's are 4 ohms each, run them at a 2 ohm load together, but otherwise, don't worry about them much. You could run them together at 4 ohms, but then each would only get 40 watts or so rms. Which would be good for balance reasons - if you want that. It'll have a more focused front setup rather than behind overpowered by the rear. Several ways you can do it.

Run the two subwoofers at a 2 ohm load, which will get approximately the right amount of power to them.

Set the gains correctly for all of these, and you'll be fine. You're using the amp for less overall power than you need, so you won't need to worry.

 

[gunz4me 10+ year member]

I am going to have to burst your bubble if you think your Infinity Kappas are true 2 ohm drivers. The DC Resistance on mine measures at 3.1 ohms, so your Infinity Kappas are more like 4 ohm nominal!

 

[Plutoman 10+ year member]

I am going to have to burst your bubble if you think your Infinity Kappas are true 2 ohm drivers. The DC Resistance on mine measures at 3.1 ohms, so your Infinity Kappas are more like 4 ohm nominal!

Really?

Most of them I've seen are 2 ohms. But that isn't horrible, either. As long as the gains are set correctly, it's not a problem. The amplifier will put out enough power, I'm pretty sure, to satisfy him over the bose system.

 

[gunz4me 10+ year member]

Really?
Most of them I've seen are 2 ohms. But that isn't horrible, either. As long as the gains are set correctly, it's not a problem. The amplifier will put out enough power, I'm pretty sure, to satisfy him over the bose system.

Meh, a complete Sony Xplod setup can be tuned to sound better than most Stock Bose systems. //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif The Bose philosophy seems to be to take the cheapest driver known to man and equalize the piss out of it to force it to perform to their "acceptable" standards.

This is the industry standard that sums up most Bose car audio setups: No highs, no lows, must be Bose!//content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif