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Discussion Starter #1
Okay, soo lets say I have sub.. 4 ohms and a 100 watt rms rating (yes, very small), and an amp.. 4 ohms putting out 50 watt x 2. If I were to "bridge" the amp, would it put out 100 watts rms to the sub?. Also, does anyone have a good diagram on how to bridge a two channel amp to a single sub?.

I realize similar questions like this have been asked before, but I need to make damn sure before I go and spend my hard earned money.

Thanks for any and all help.
 

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First you need to make sure your amp is bridgeable, most are some aren't. Look and the terminals on you amp. It will tell you for bridging what post to use for the positive and which one for the negative.

You then simply connect the wire on the negative terminal to the negative post on the sub and the positive on the amp to the positive on the sub. Very simple set up.



When bridged the amp should produce 100 rms to 1 channel. This is true for most amps, the specks sheet on it would confirm this.
 
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You'll be seeing more than 100w. Most bridgable amps work like this: if they're 50x2 @ 4 ohms, they'll usually be 75-100w @ 2 ohms. Bridging the amp will give you the combined 2 ohm power, so it would output 150-200w bridged.
 

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Yea. There is really no definite answer to how much it will put out with out looking at the specks for the amp. ^^^^^ He is right. It should definitely put out 100 but could be more.
 

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Discussion Starter #7
Here is the amp I'm looking at. There's no brideged rms/ohm rating listed. I know the obvious.. small as hell, no name brand, etc.. but with a two year warranty and $55 shipped to my door, it's all I need. I want to hook it up to a passive Bazooka tube a buddy of mine has, I believe it's the one found here. I'm just looking to put a little bit of low end in a Sportage I recently picked up for a grand.

You'll be seeing more than 100w. Most bridgable amps work like this: if they're 50x2 @ 4 ohms, they'll usually be 75-100w @ 2 ohms. Bridging the amp will give you the combined 2 ohm power, so it would output 150-200w bridged.
So you're saying that'll it'll be 75-100w bridges at 4 ohms and 150-200w at 2 ohms.. correct? If I hook that amp to that sub above, will it automatically know that the sub runs at 4 ohms and thus give it the 75-100 watts?

EDIT: And although it says that amp is bridgable, there are no "markings" on how to bridge it like I've see on other amps.. hmm.
 

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You should be good. It's listed as bridgeable and it's obviously two ohm stable, so I don't see any problems in bridging both channels to one four ohm sub.
 

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What I'm saying is, if its 50x2 @ 4 ohms, then it will probably be about 75x2 at 2 ohms. Maybe more. When you bridge a 2-channel amp, it gives you the summed power of the channels at 2 ohms. So, if we say its 75x2 @ 2 ohms, that would make it 150x1 @ 4 ohms bridged.

What kind of amp is it? Link us up!
 

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That amp will give you 300 peak watts when bridged to one 4 ohm sub. It will give you 200 watts rms when bridged to a single 4 ohm sub.
 

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Yea that amp will most likely blow your sub...I suppose you could turn the gains and bass boost all the way down and be careful on how loud you turn up your radio...
 

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I say go for it. You won't find too much smaller of an amp, especially not for that cheap. As stated above, drop the gains and bass boost way down and you should be good.
 

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rofl at Boss. You'll be lucky to get 100w out of it.
 

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Yea go for it. Tune it so it sounds good, and leave the gain down. I didn't notice it even having bass boost so I would just get it, leave the gain down a bit and let it bump.
 

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A little excess power is a good thing. It increases what is called dynamic headroom. In other words, when the music has transients or peaks (moments that are louder than others), the amp has the extra power to reproduce transients without distorting. A little too much clean (undistorted) power is much better than too small of an amplifier being constantly over driven.
 

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Discussion Starter #18
Seriously, you guys make this one of the best forums on the interent. Thanks for all the help.

I decided to spend a little bit more money and pick up a 10" Clarion rated at 300w rms and a Dual 460w amp that puts out 300w rms when bridged, dropped in a sealed box. Three times the power, only about $40 more and with my tax return coming, why not?.

But thanks for all the help guys.. I've learned a little bit in this thread.
 

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That is why we have threads and why we are all members here on this one. You'll like that Clarion. I have had one in my Focus for about a year and a half. I like it. And what they said about clean power is totally true. I have had mine running off a 300 rms and 600 peak and it sounds great and never distorts.
 
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