Bridging Amp to Power Subs

New member

Username: Quietbeats

Austin, Tx
USA

Post Number: 1
Registered: Feb-08

Posted on Wednesday, February 20, 2008 - 09:26 pm:

I have two 12" 4 ohm dvc kicker cvrs and just purchased the profile ap2000 amp to power them. The subs can handle 400w rms apeice. The profile is a two channel amp that puts out rms power of 320w x 2 @ 4 ohm, 480w x 2 @ 2 ohm, and 960w x 1 bridged @ 4 ohm. Now, I always hear people talking about bridging two channel amps to power (2) subs. Is there any distinctive advantage to wiring my subs to 4 ohms and powering them with the amp bridged as opposed to just having them each wired to 2 ohms and powering one sub with channel 1 and the other sub with channel 2? The latter would be much easier for me considering my subs are already in the box with the coils wired parallel making each sub 2 ohms, but hearing all the talk about bridging 2 channel amps instead of running the subs on separate channels drives me to seek a second opinion. Any advice is greatly appreciated.

Gold Member

Username: •cam•

BC
Canada

Post Number: 1979
Registered: Nov-06

Posted on Wednesday, February 20, 2008 - 09:40 pm:

Bridge if you can but I wouldn't worry about it. Like MS said in the other thread, you need to bridge it if you don't have any sub-dedicated low-level outs from your HU.

Gold Member

Username: Van_man

Boston South, MA

Post Number: 3456
Registered: Mar-06

Posted on Wednesday, February 20, 2008 - 09:42 pm:

in your case, it doesnt really matter, You wont gain anything by bridging it. Some ams put out more power bridge, but yours is a wash. Nice Subs.

Gold Member

Username: Van_man

Boston South, MA

Post Number: 3457
Registered: Mar-06

Posted on Wednesday, February 20, 2008 - 09:47 pm:

"Like MS said in the other thread, you need to bridge it if you don't have any sub-dedicated low-level outs from your HU."

What does that have to do with bridging? Even if its a full signal, the sub amp (LPF) will cut the highs, Low level outs dont factor into bridging..Did I miss something?

Gold Member

Username: •cam•

BC
Canada

Post Number: 1982
Registered: Nov-06

Posted on Wednesday, February 20, 2008 - 09:49 pm:

I'm talking about the mono signal.

whYTee

Silver Member

Username: Spankinurwoofers

GR, MI
US

Post Number: 277
Registered: Nov-07

Posted on Wednesday, February 20, 2008 - 09:50 pm:

arent sub outputs usually mono, and others stereo? i think that's what he was talking about 'sub-dedicated low-level outs'

as long as both channels would be putting out the same signal(from a mono source) it should be ok ...correct me if i'm wrong tho

Gold Member

Username: Van_man

Boston South, MA

Post Number: 3458
Registered: Mar-06

Posted on Wednesday, February 20, 2008 - 10:03 pm:

...2 ohms stereo...
...4 ohms bridged mono...

So if each sub is on its own channel wired to 2 ohms, it will get a stereo left and stereo right sub signal, as opposed to having it bridged and left and right channels merged to a single mono signal. is that what you mean?

I thought sub signal was a mono tone signal, recorded in mono tone, there fore, it was not a stereo signal and it would not matter wether it was played on a left speaker or a right speaker. it would still be the same signal. If that was the case, wouldnt the sub volume have a left and right balance? Instead off volume?

New member

Username: Quietbeats

Austin, Tx
USA

Post Number: 3
Registered: Feb-08

Posted on Wednesday, February 20, 2008 - 10:17 pm:

I have an alpine 9886 HU with rca subwoofer preamp outs, built in crossover, and subwoofer volume control on the head unit itself. I don't know if that will help you guys to come to some consensus but as of now I'm still not convinced of what to do. There seems to be some discrepancies between posts, Thanks

Gold Member

Username: •cam•

BC
Canada

Post Number: 1983
Registered: Nov-06

Posted on Wednesday, February 20, 2008 - 10:18 pm:

What?

That was confusing.

Like you said, the signal in each subwoofer RCA will be identical to the other. Since bass is non-directional in a vehicle cabin, he wants to drive the subs with identical signals so that waves reinforce each other as well as possible by being as close to identical as possible.

Err. I think I got all of that right. The basic idea should be correct.

I've probably missed the idea completely.

Yeah. Sub outs should be mono, so I said that if he didn't have those he should bridge the amp to get a mono signal.

Gold Member

Username: •cam•

BC
Canada

Post Number: 1984
Registered: Nov-06

Posted on Wednesday, February 20, 2008 - 10:19 pm:

I was saying "What?" to Marc.

Yeah you can do it either way then. Using separate channels would get you more terminals, so that might be easier. No jamming 2 wires into a single terminal.

Gold Member

Username: Van_man

Boston South, MA

Post Number: 3463
Registered: Mar-06

Posted on Wednesday, February 20, 2008 - 10:21 pm:

ok I say bridge it. Running the amp at 4 ohms will be better on the amp.

New member

Username: Quietbeats

Austin, Tx
USA

Post Number: 4
Registered: Feb-08

Posted on Wednesday, February 20, 2008 - 10:22 pm:

Excellent, thanks guys. You've been very helpful, and done so very quickly. I just joined, but I can already tell this is a great forum. I will be back.

New member

Username: Quietbeats

Austin, Tx
USA

Post Number: 5
Registered: Feb-08

Posted on Wednesday, February 20, 2008 - 10:26 pm:

Ugh, marc. I thought I had this resolved. Is it really worth my trouble to tear my whole box apart and rewire everything (not to mention drilling a hole in the wall dividing the 2 chambers of my box to run wires through) just so I can run this at 4 ohms instead of 2, even though the amp is 2 ohm stable?

Paul Larrea

Platinum Member

Username: Wingmanalive

A pic is worth
1000 posts!!

Post Number: 13951
Registered: Jun-06

Posted on Wednesday, February 20, 2008 - 10:26 pm:

It's great here.

Gold Member

Username: Van_man

Boston South, MA

Post Number: 3464
Registered: Mar-06

Posted on Wednesday, February 20, 2008 - 10:29 pm:

no its not.

"in your case, it doesnt really matter, You wont gain anything by bridging it. Some ams put out more power bridge, but yours is a wash. Nice Subs."