Good amp for 6 speaker system?--2 coax front, 4 coax rear

[Dave Mancuso]

Hi guys!

OK--I have a system with 2 Polk db570s in the front and (soon) 4 db 570s rear. The rear speakers are wired serial-parallel (I have to verify this with a VOM, but I'm pretty sure this is the case). So I have 4 ohms in front for 2 speakers and four ohms in back for 4 speakers.

My question: if I get a four channel amp, should I get a 55-60 rms x 4, or do I need to go higher, like 80x4?

I don't need huge sound, but I do want to feed my speakers properly. I was hoping to get a good amp for under $200, but it seems that I can't find a 60x4 under about $250 (looks like no one likes cheap Sonys @$150--I guess you get what you pay for). I'd go used if I could trust that my purchase wasn't driven within an inch of it's life.

If I got a 60x4, the front speakers would be perfect at 60, but each of the rear speakers would be getting 30 (all minus 20% waste/heat, right?). The speakers are 60 watts rms, so I don't know if it's enough to put 30 through them, but I hope so. Conversely, I dont' know if it's OK to put 80 through the fronts--I guess I could turn the gains down if I have controls for each channel front/rear.

I don't need my car to shake going down the street, so loudness/killer bass is not my thing. I guess I just want full sound that I can feel just a bit if I want to turn it up some.

Oh--I thought about rewiring the rears in just parallel to get them to 2 ohms, so that the rear channels get a little more power from the amp (60 at 4ohms could be 75 at 2 ohms in some specs I've read)--but I'm trying not to alter the wiring system, and the speaker specs only list 4 ohms, not 2 (does that mean that the db570s don't want 4?).

From reading the forums, I'm looking at Alpine, Hilfonics, MTX, RF, etc.

I have a little amp driving a sub, but I'm not really counting it much in my design--it's a 30wx2 amp bridged into mono with a 10 inch sub--pretty crappy little sub, actually. I should upgrade it, but the above system comes first.

A side note--it's funny to me that the "blackout mode" on my Apline 9805 head unit turns off the display to give the built-in amp more juice. Is the display that power-hungry, or is the built-in amp just that weak? Maybe both.

Thanks again for your help--your answers on my first question about my system's clipping got me this far.

[sntnsupermen131]

1. you dont want it louder in the back than you do in the front...it messes up your soundstage and jacks with the way it sounds
2. dont put the speakers on a 2ohm load
3. its always better to have a bigger amp than a small one...itll be cleaner, you wont have to drive it as hard, and itll last longer
4. the more i hear about alpines, the more i dislike them, but i dont really know the answer to your question about your head unit
you can put 80 watts on your fronts...the polks will handle it
my mm6 components are rated at 150....i have 215 going to them...sound great
-Cody

[MTXMAN]

of the brands you listed i'd say hifonics or rf, mtx has power but it's realy not clean enough for interior speakers, and i'm not too big a fan of alpine...

[Dave Mancuso]

OK--80 per channel makes sense. I found some great prices on justamps.com for Crunch (V Drive V4200@$124.99) and Profile (California CA640--75x4 @$114.99). Can these amps be any good for these prices, or maybe justamps isn't an authorized vendor?

[MTXMAN]

dude if you want good sound quality for your 4ch pay 100 more and get this
http://www.speedsound.com/tek9.asp?p...ific=jmrrfpnpm

Hifonics ZX 6400
85x4@4ohms

and a good one for the mm6...
http://www.speedsound.com/tek9.asp?p...ific=jmrqooomk

Hifonics ZX 6000
150x2@2ohms - $284

both of these are from an authorized dealer www.speedsound.com who also happens to be listed with the betterbuisness bureo and both are a little over half of msrp, both run over 500 each at most stores.

that's the best non ebay deal i saw after looking for a little while. and while they are a little more expensive than the ones you listed, they are well worth the difference. i wouldn't go with the crunch in general and while profile's not bad the hifonics will sound better enough to be well worth the price difference