bridging an amp

[97lude]

how would i bridge a 4-channell amp? a guy has got one he says can be bridged to 2x400 watts. could i do that to power my 12's 300 rms?

[carbon_crash]

are you just running two subs?

[97lude]

yes

[BanginJimmy]

to bridge it, if both sets of channels are bridgable, then it will be positive from channel 1 and negative to channel 2 to sub 1. Then positive from channel 3 and negative from channel 4 to sub 2.

To do this you will need to have both subs in seperate enclosures because theres no way to know if both channels will be ther same.

[97lude]

vtec siad i can tie the 2 + wires together and the 2 - together and run them off of one channell and why would u have to have 2 boxes alot of people have bridged amps withot 2 boxes.

[BanginJimmy]

if both subs are getting their signal from 1 set of channels, then thats fine. But because you would be using 2 sets of channels thee signal wont be exactly the same and could damage the subs.

[97lude]

but why would i need 2 boxes

[redgst97]

It depends on the gain set-up of the amp.

If channels 1 and 2 use a gain, and channels 3 and 4 use a seperate gain, there is no (easy) way to tell the the gains are set 100% identical. If they are on seperate gains, and channels 1/2 is set at (say) 50% gain, and channels 3/4 is set at (say) 55% gain, the the 2 woofers will move differently. ONLY slightly, but enought to definately alter the sound (how much?? Not sure), and possibly harm the woofers. With a voltmeter and some knowledge you can get the gains close. With an osciliscope, you can get a LOT closer.

With all THAT said, just make seperate chambers for the 2 woofers....save some effort. OR, you could get an amp better suited to run woofers....

[97lude]

another thing if i wanted to run 2 dual 4ohm subs to a mono 1 channell amp i would put + and- on one then the other and then run extra + + to + on amp and - - to - on amp correct? also i get different answers the guy at circuit city told me i needed to get an amp with 350 rms at 1 channell 4 ohm to power my 300 rms subs. he siad that in the descrip. when it says 300,350, etc. rms at 4 oms iot means to each sub is that true? or do i need one that has at least 600 rms in descrip. for 1 channell?

[BanginJimmy]

what subs are you planning on running?

Are you buying them already in a box?

If so, is the box already wired up?

what is a budget for an amp?

[97lude]

the subs are mtx 5500's i have a sealed box nd it is not already wired boght the box seperate. no budget yet not looking to spend $50 and also not looking to spend $500. About my question too does the amp have to be 600 rms 1 channell at 4 ohms or does 300 rms in the amp descrip. mean to each sub?

[BanginJimmy]

ok the subs are 300wrms each. If you have 2 of them, then you will want an amp that does 600wrms at either 1 or 4 ohm.


http://mobile.jlaudio.com/graphics/Support/Tutorials/wiring_images/DVC_Parallel_2.gif

http://mobile.jlaudio.com/graphics/Support/Tutorials/wiring_images/DVC_Series_2.gif

[97lude]

thanks man i thought so the guy at circuit city seemed like he didnt know what he was talking about. that amp put out 350rms at 1 channell 4 ohms therefore it wouldnt have been enough power any suggestions on an amp. what about the hifonics brutus 1600 it has 550 rms at 4ohms to much huh?

[BanginJimmy]

that would work, and allow you ALOT of room for upgrade, but no you really dont need something that strong.

you will want an amp with specs something like this one. Its a very nice amp BTW
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=430

or if you want an MTX to match the subs
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=3349

[97lude]

id have to bridge the orion right? what about the ma audio m1889i ? the specs say 1x 400wrms 4ohm mono. the price is very good also.

[BanginJimmy]

400 rms will be fine. Theres nothing that says you have to use evcery bit of power handling a sub has.

that amp should work fine. I have no experience with MA Audio though to tell you about their dependability

[BKgen®]

So... if you are going to bridge a 4 channel amp to 2 12's that you already have in a box (ported.)..
Let's say you have something like this-->http://akamaipix.crutchfield.com/products/2005/044/h044H1210DS-f.jpeg.

couldn't you just fabricate a wall to split the port in half so you wouldn't have to build 2 boxes?

[BanginJimmy]

no you cant. It will change the tuning considerably. Also you will never be able to match the finish of the box exactly and it will look retarded.

[BKgen®]

just a thought.

[vTeC]

Easy way to remember is Left Positive, Right Negative. Normally amp channels are labeled from left to right. Left would be the first channel, right the second. Same for the third and fourth channels. So I've always remembered it by left positive (first channel) and right negative (second channel). The biggest thing to remember is that the ohms need to match up. If you are running DVC subs, then you probably can't get the amp to run stable. It get hot, cut off, and eventually ruin it. Best thing to do is get a high-current amp. These amps run less ohms when bridged. An example would be a 2 channel high current that would run 2 channels @ 4 ohms or 1 channel bridged @ 2 ohms. These amps are much more efficient because there is less resistance at a lower ohm.. (ohm=measure of resistance). So I would always go for a high current amp when running 2 or more subs, unless they are just single voice coil, but you could also wire dvc's to run at a higher ohm, but it's just not as efficient as being at the lower ohms. Feel free to pm if you need help. Hopefully this will be useful to you.

[BanginJimmy]

The biggest thing to remember is that the ohms need to match up. If you are running DVC subs, then you probably can't get the amp to run stable.

most mainstream subs can be had in dual 4 ohm coils. 2 DVC 4 ohm subs can be wired series/paralell to 4 ohm.


Best thing to do is get a high-current amp. These amps run less ohms when bridged.An example would be a 2 channel high current that would run 2 channels @ 4 ohms or 1 channel bridged @ 2 ohms


high current amp means high current. It doesnt mean it will run at a lower ohm load. An amp thats stable to 4 ohm stereo IS NOT AND NEVER WILL BE stable to 2 ohm mono.


So I would always go for a high current amp when running 2 or more subs, unless they are just single voice coil, but you could also wire dvc's to run at a higher ohm, but it's just not as efficient as being at the lower ohms.

Why dont you use a mono amp? :???:
Why cant you wire DVC subs in paralell and run a lower load? :???:



Never listen to this guy, hes an idiot. :screwy: