4 channel vs. 5 channel amp

[Crpediem2]

I have learned alot from this board so far. I am building my system for my new car. should I go for a 4 channel amp to power the from speakers and mono to the sub with the HU powering the rear speakers or go for a 5 channel amp to have 4 independent channels to front and rear with mono sub? I know rear fill is just fill, but should I have it powered the same as my front speakers? these are the amps i am considering. thanks for the help.

4 channel:

KENWOOD EXCELON DIGITAL XR-4S 4 CHANNEL 480 WATT NEW 10 - eBay (item 250611859588 end time Apr-15-10 09:48:32 PDT)

5 channel:

Alpine PDX-5 PDX5 5 Channel car Amplifier 08 - 09 model - eBay (item 400115088064 end time Apr-22-10 13:23:36 PDT)

I am looking for a small amp to go under my passenger seat.

Click to read more...

 

[Qbenjamin 10+ year member]

My opinion is a bit biased, but I would say to go for the 5-channel. I ran a Memphis Belle for years, and the ability to have everything all-in-one, was great for me. It really doesn't make a difference if you use a separate amp for your speakers/subwoofer(s), it is completely user preference. If space is an issue, then obviously you want to go for a 5-channel.

 

[gunz4me2 10+ year member]

Unless Alpine has updated their PDX-5 in the last few years, I'd say to look to another alternative. I was going to buy one used from a friend in 2008, until I installed it. The front and rear channels exhibited loads of HISSSSSSS, no matter where the gains were set and the sub channel was uber weak at 2 ohms. In fact, the sub channel was so weak, it was like I didn't even have a subwoofer installed in the car. I was totally underwhelmed and regretted taking 20 minutes just to unhook what I had to try out that POS Alpine.

Going further, the sub channel was easily outperformed by an Orion HCCA 225 G5 bridged to 2 ohms and rated for 200 watts RMS at 2 ohms. Granted, my process to judge output was not scientific, but, I could at least hear the sub with the lower powered Orion versus having to crank the hell out of the Alpine's subwoofer gain and driving the sub channel into audible distortion levels. Granted, there could have been something wrong with the Alpine's sub channel, but I wasn't going to take the time to BUY another one to try.

 

[Wingman0121 10+ year member]

I had a Viper 1100.5 5 channel amp that did 75 watts x 4 RMS into 4 ohms and 600 watts x 1 RMS into 1 ohm for the sub channel. It is nice and big and runs a car load of speakers but I did run into an issue... during a hot summer day the amp might overheat if you play the sub channel really hard, because it is still sharing the same heatsink as the 4 channel amp. Mine overheated a few times and stayed too hot to touch throughout the whole summer, but I ran it really hard.

 

[gunz4me2 10+ year member]

I had a Rockford Fosgate 25 to Life Power 1000. It was underrated, worked great, BUT it was H U G E. I got tired of trying to figure out ways to shoehorn it into the trunk of my 2006 Rustang, so I gave it to a friend of mine. It is his problem now, bahahahahaha

This was one of the iterations of it that amp/install I didn't care for:

 

[Bumpin' Goalie 10+ year member]

I'm a big fan of just fronts with no rear fill at all. Imaging purposes //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

Though it's up to you.

The PDX's are hard to beat for size compared to other monstrous 5chan's. And they tend to stay pretty cool.

If you decide on a 4 channel, it can open up a lot of options and many are very small.

 

[Qbenjamin 10+ year member]

Every since I got the PDX's, I can't imagine going back to the huge amps again.

 

[Crpediem2]

Bumpin,

What do you think of the Kenwood Excelon xr-4s? Or do you have another suggestion for a sub $400 amp I can mount under my seat?

 

[timaishu 10+ year member]

I run an Infinity 5350A and I love it.

You mentioned using a 4 channel to power the fronts and the sub while using the HU to power rear fill.

You can still do the same with a 5-channel. I have my front and rear bridged for 120wRMS at 4 ohms and 300wRMS at 2 ohms for the sub channel. The front and rear individually will do 50wRMS at 4ohms or 60wRMS at 2 ohms.

THis is my first amp and I dont really see myself replacing it unless I find the need for a more powerful 5-channel. 300wRMS is enough for me. Its split down the middle for my IDQv1's so they each get 150 which is plenty for them. They are rated at 200rms.

Sounds fantastic. No hiss or anything. Ive had it for 2 years now.

 

[stocker08 10+ year member]

Memphis Big Belle. Would never go back to running two amps. It can run under a bunch of different applications and it has awesome power.

 

[gentlejax 10+ year member]

Xtant 3300x ...made in USA old school SQ.....is made to run 3 or 5 channel....rear channels will be slightly less watts as the front(as it runs them rear fill) ....stout amp ...and for sale....you should check into it.....I am selling one