Bridging the door speakers?

[RedKatanax9]

My new 4-channel Alpine F240 is running really hot, almost too hot to touch, after only 20 minute of driving. So I am wondering about my wiring scheme and wanted to get you guys' opinions.

I have Infinity Reference 6802cf 6x8s up front, and pair cheap Pioneer 5.25 G1340 in the back for rear fill. They are wired parallel, in bridged mode, from the Alpine. Input to the Alpine is two channel with two Y splitters. I can't fade front and back but the staging is just fine. The Alpine is 40x4 or 100x2 bridged. I didn't think the speakers are that much of a burden on the amp, but it gets unusually hot...Should I not bridge them? My Alpine M350 mono amp driving 2 JL 10" in parallel runs sooo much cooler, maybe 1/10th as hot as the F240.

The Infinity recommended power range is 2-60 rms, while the Pioneers are 2-25.

Here are the links to the specs if you need them.

Alpine: http://www.crutchfield.com/S-J3qENh....asp?g=120&id=features_and_specs&i=500MRPF240

Pioneer: http://www.crutchfield.com/S-J3qENhtBLCo/cgi-bin/ProdView.asp?g=51800&id=essential_info&i=130TSG1340

Infinity: http://www.crutchfield.com/S-J3qENhtBLCo/cgi-bin/ProdView.asp?g=52200&I=1086802CF

Thanks guys.

 

[mauricec00]

i dont get it your amp is hot? or the deck?or the speakers?

 

[chuyler1]

You're going to fry the amp with that configuration, hence why it is so hot. That amp supports 4-2ohms x 4 (or 4ohms x 2 bridged). Lets do some math...

Two 4ohm speakers wired in paralell yields 2ohms.
2ohms across a bridged channel yields 1ohm per channel.
1ohm per channel = fried amp.

Bridging is ok, but you need either 1 4ohm speaker or 2 8ohm speakers. (or 3 12ohm speakers etc...)

You have two choices, 1) only connect your front speakers to the amp in a bridged fasion or 2) connect all four to an individual channel. You could also wire the speakers in series instead of parallel but that wont give you any more power and you loose the ability to fade from the front to rear.

 

[RedKatanax9]

i dont get it your amp is hot? or the deck?or the speakers?

??? I don't get it either.

 

[RedKatanax9]

You're going to fry the amp with that configuration, hence why it is so hot. That amp supports 4-2ohms x 4 (or 4ohms x 2 bridged). Lets do some math...

Two 4ohm speakers wired in paralell yields 2ohms.
2ohms across a bridged channel yields 1ohm per channel.
1ohm per channel = fried amp.

Bridging is ok, but you need either 1 4ohm speaker or 2 8ohm speakers. (or 3 12ohm speakers etc...)

You have two choices, 1) only connect your front speakers to the amp in a bridged fasion or 2) connect all four to an individual channel. You could also wire the speakers in series instead of parallel but that wont give you any more power and you loose the ability to fade from the front to rear.

Hmm, that makes sense. I just thought the speaekers don't draw too much power. Another dumb mistake. (chair) I think I am going to wire each speaker into an individual channel and see how it goes. Thanks Chuyler, U da man!

 

[Poseur]

Personally I'd highly recommend bridging amp to the front speakers, and then runnign the rears off of the deck power for 2 reasons, firstoff, this jsut sounds better period, but also for the fact that your speakers are only rated for 25w, which is close to what you can get out of the deck. so they'll be playing happily, and then you can use that extra power for pushign upfront. added bonus, you can still fade. oh, and by the way, DO NOT BRIDGE YOUR HU

 

[chuyler1]

I agree, which is why I listed it as option 1. I am running fronts of a 75x2 amp and running stock speakers off the stock HU for the rear (You don't hear them at all up front which is how I like it). I guess didn't mention running the rears off the HU though (I make too many asumptions (doh) ). And good point Poseur, with all this bridging frenzy it is good to remind people that you cannot bridge the HU.

 

[RedKatanax9]

All of my speakers go through a Pioneer DEQ-9200 processor, it basically separates input from HU into three channels, tweets, mids and lows, as well as controls volume. So I don't want to run anything off the HU directly, kinda messes up the whole setup... It wold otherwise be a good idea.

I just rewired the 4 speakers coming off 4 channels from the amp. I've noticed the overall volume is a little bit lower, maybe 2-3 db. Hmm, I might just hook up the fronts in bridged mode and forget the rear speakers...but I like having the rear fill.

 

[chuyler1]

Rearfill is for amateurs. Unless you've got a DVD player and 5.1 surround sound they are useless.

 

[FrigginGLI]

Rearfill is for amateurs. Unless you've got a DVD player and 5.1 surround sound they are useless.

Yea you don't need rears.

 

[Iggy]

i just got my first aftermarket stereo in my car and I cant stand the fact that I only can hear music from the front.

I have my Infinity components up front and my JL subs in the back powered by my amp with my stock speakers in back powered by my HU. I just bought a set of infinity speakers for my rear deck and im going to ditch the subs in place of those.

for those audiophiles who only have front speakers amped, how do you overcome only being able to hear music from the front?

 

[chuyler1]

When you go to a rock concert you stand facing the band. When you go to a jazz club, you sit facing the musicians. When you go to the opera you face the stage. Why would you want music coming from the rear?

If you setup your front stage properly you should be able to pin point the musicians on your dash. You can pick out the exact location of cymbals and toms on the drum kit. When you hear multiple singers you know which one is to the right and to the left. If you have sound coming from the rear it distorts this entire perspective.

Ok, I'll admit, if you go to a club music comes from all over...but I don't go to clubs so that doesn't apply to me.

 

[tsunami]

i can barely hear the speakers in the rear.... stock speakers from stock hu.... but i love the boston Z's i have up front... those things give out such kick ass clean sound that i would think the rears actaully bring down the sound quality in my car...

 

[RedKatanax9]

When you go to a rock concert you stand facing the band. When you go to a jazz club, you sit facing the musicians. When you go to the opera you face the stage. Why would you want music coming from the rear?

If you setup your front stage properly you should be able to pin point the musicians on your dash. You can pick out the exact location of cymbals and toms on the drum kit. When you hear multiple singers you know which one is to the right and to the left. If you have sound coming from the rear it distorts this entire perspective.

Ok, I'll admit, if you go to a club music comes from all over...but I don't go to clubs so that doesn't apply to me.

The music sounds great in the front seat, I just like my backseat peeps have some good tunes as well. But then if it compromises the overall SQ I am gonna just get rid of rear speakers. I am gonna try it out first. Thanks, man.

 

[khaosman]

Here is what I recommend you do:

amp your front speakers (bridged if they can handle it)
power your rear speakers off of HU

When you are cruising alone, fade to the front. When buddies hop in, fade it to the middle. Best of both worlds! Or put a high pass filter on your rear speakers around 200-500hz...

 

[1sty]

Tell the passangers in the back that if they were worth a damn, they'd be in the front with the music, so shut the hell up already.

 

[memo79]

(rofl)

 

[Poseur]

You know I don't see why everyone seems ot think that a front-heavy soundstage produces NO sound for rear seaters. Honestly I've sat in the back of my car and had a listen to thigns, and it actualyl sounds pretty damn good. definately better than what havingacouple of coaxes downin the bottom doors would be, and WORLDS better than the 6x9 blaring at the back of your head that you get from the backseat of many cars.

 

[1sty]

Yeah, if they can't hear it, its just not loud enough

 

[RedKatanax9]

yeah, the rear door speaker are out cuz the backseat peeps are not worth a damn!