car audio. Sorry I know this isnt a car audio site

[zumbo]

Well, although the alpine's I'm using are class D amps, I know quite a few who use A/B and are doing fine on stock electrical. It just depends on the user, the car, and how they install it.

In this case, I think it depends more on what is inside the amp. They are pretty on the outside though.

Inside a LP
http://www.auctiva.com/hostedimages/showimage.aspx?gid=754095&image=142966573&images=142966558,142966565,142966573,142966586,142966590&formats=0,0,0,0,0&format=0

 

[GlocksRock]

What about bi-amping your fronts with a full active system? use each channel for a speaker? This would sound much better anyway. I have an Alpine PXA-H400 digital crossover on craigslist that would work perfectly

1500 watts rms translates into about 120 amperes of current draw at 12.5 volts. with amplifier efficiency at say 70% that would put current draw at 156 amperes at full output. Since, at a moderate output level (95-100db), with music, one uses about 25% of that as a high conservative estimate, it puts current draw at around 39 amperes. Most stock electrical systems would have no issue with this amount of draw, especially since it is not constant.

Upgrading the main three electrical/current sections of cable (Alt. to bat.; bat. to chassis; chassis to eng. block) in the vehicle along with a high output battery addresses most current flow issues. Adding one of the large hybrid type capacitors from Stinger or Alumapro does not hurt at all either.

I have thought about going active, but I don't really have much room left for any new/extra gear, and it's already installed so I don't feel like redoing it all over again, I'm pretty much out of money to spend on car audio now as it is.
As far as the amps efficiency, the sub amp is 64% and the 4 channel amp is 68%. Not sure if you have looked at the pics of my system, but I also have 2 1 farad capacitors, but I am also well aware of the big debate on those as well. But since I already had them, and I like they way they look, I put them in. I am also familiar with doing the big 3 as you mentioned... can I use 4 guage for that since that is what I'm using in the rest of my system, or should I go with a heavier guage for the big 3?

 

[annunaki]

The new JL amps are pretty slick and small as well.

Full range class D has it's advantages

 

[GlocksRock]

Yeah, they are nice... but I spent a total of $480, shipping included on both of my brand new amps, so I'm pretty happy with the performace I'm getting for the money, plus each one carries a 5 year warranty, which is nice too.

 

[annunaki]

I have thought about going active, but I don't really have much room left for any new/extra gear, and it's already installed so I don't feel like redoing it all over again, I'm pretty much out of money to spend on car audio now as it is.
As far as the amps efficiency, the sub amp is 64% and the 4 channel amp is 68%. Not sure if you have looked at the pics of my system, but I also have 2 1 farad capacitors, but I am also well aware of the big debate on those as well. But since I already had them, and I like they way they look, I put them in. I am also familiar with doing the big 3 as you mentioned... can I use 4 guage for that since that is what I'm using in the rest of my system, or should I go with a heavier guage for the big 3?

4 ga. should be sufficient unless you plan on going bigger in the future.

 

[unreal.freak]

Anyone ever used the PPI amps? Ive seen and heard good things about them

 

[efzauner]

Sorry again but I would really like some help on my truck. I was thinking about polk db6501 for the front and db651 for the rear. Also a mtx amplified thunderform subs with a kenwood kvt-512 head unit. Does any one have polk in their car and what do they sound like? Also any recommendations for other speakers for a total price of $600 or less just for the speakers, not subs and headunit. I already have factory tweeters with four door speakers. Thanks for any help

I spent a few years in the car audio biz.. The polks are quite nice and are pleny if you are just going to hook em up to a stock radio or an afternmarket unit. Alpine, pioneer, etc make fine head units. But if you want good audio you really need to get a subwoofer and an external power amp. Dont bother putting anything in the rear unless you travel regularly with friends that love to hear it LOUD in the back. Just like home audio, the front are where its at.
Get a good deck with rca outputs for extrenal amps and a subwoofer.
I suggest you visit a good car audio shop and get advice plus a good install.