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How to I wire a dual 4 ohm sub to a two channel power amp without bridging it??? Can I just put one channel in on side of terminals and the same to the other side??? I know it's a dumb question but bare with me here people:(
 

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How to I wire a dual 4 ohm sub to a two channel power amp without bridging it??? Can I just put one channel in on side of terminals and the same to the other side??? I know it's a dumb question but bare with me here people:(
Yes, connect one driver to one channel of the power amp and the other driver to the other channel of the power amp. Then run the same LFE "sub" signal to both inputs of the power amp.

Does that answer your question?

Edit: See post #4 for more complete answer.
 

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Discussion Starter #3
It's only one sub, it's going to be an 18" basically how can I wire a d4 sub to a 2 channel amp without bridging it?
 

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It's only one sub, it's going to be an 18" basically how can I wire a d4 sub to a 2 channel amp without bridging it?
Most common way is to tie the terminals together on the speaker in either series or parallel wiring, then tie that to one output channel of the amplifier.

Identify each coil with an ohm meter so you know which terminals go to which coil. You can often tell by the way the terminals are arranged on the speaker.

For series voice coil wiring, wire power amp out L black to voice coil A black, then tie voice coil A red to voice coil B black, then wire voice coil B red to amp out L red. Only one channel of the power amp is used. This is most common and safest.

For parallel voice coil wiring, the two reds on the speaker would be tied together and the two blacks on the speaker would be tied together, then the blacks on the speaker are wired to the black for the amp left channel output and the reds on the speaker are wired to the red for the amp left channel output. Again, only one channel of the power amp is used. This is pretty safe, but you have to know that the amp can drive the parallel value for the voice coils, in this case 2 ohms. If the amp is not rated for 2 ohm load, don't try it.

If you really need maximum power, you can do what I suggested above:
  1. Identify each coil with an ohm meter so you know which terminals go to which coil.
  2. Wire from amp out L to coil 1, amp red to coil red, amp black to coil black.
  3. Wire from amp out R to coil 2, amp red to coil red, amp black to coil black.
This method is generally considered experimental and not recommended except for the brave who want max power. The two amp channels have to be driven with the same signal or massive distortion and possible speaker damage can result.

Here is a pretty good guide.

Does that help?
 

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Discussion Starter #5
The first way you described to wire it, can I do that with the other coil to get the 1k watt rms to the sub? Or is it unsafe?
 

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That is hard to say. How much power can each amplifier channel deliver into 4 ohms? What is the total power the speaker is rated for? Plus that is a LOT of power for one speaker, whatever the specs say. Best not to push the limits unnecessarily.

The safe approach would be to start out with series coil wiring from one amp channel and see if it is enough. You can always go up from there, I personally like to be conservative with my equipment and make it last, so that is what I would do as a starting point.:sn:
 

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Discussion Starter #7
into 4 ohms I would think its 500watts rms for each channel is 1000 watts max and I dont have the sub but I will find one that takes 1k rms, so I want to use both channels, just power amps dont usually let you bridge without hurting it, soo im still at a standstill:/ Thanks for all the help though:) keep the ideas coming people!!!
 

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Using the 2 channels in the way we have discussed it is not the same as bridging. With each power amp output wired to a separate coil, the 2 coils would look like 2 separate loads, which should not bother it a bit. Just need to be sure the coils have been identified and connected to properly.
 

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Discussion Starter #9
okay, great I understand it, but why do I have to test the coils? its a dual 4 ohm sub so each coil is 4 ohms and the power amp is made for a 4ohm load for each channel
 

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All I mean is there are two red terminals and two black terminals, and depending on how they are arranged on the speaker it can be hard to tell which red and black go together for each coil. Just saying, be careful you don't end up accidentally wiring from amplifier left black to coil A black and amplifier left red to coil B red, etc. You don't want to cross the connections, that's all.
 

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okay, great I understand it, but why do I have to test the coils? its a dual 4 ohm sub so each coil is 4 ohms and the power amp is made for a 4ohm load for each channel
In nearly all the higher end home speakers with multiple drivers, they tend to be wired in parallel. I suspect this is because when you wire in series, the next speaker in the line is taking a signal drop from the previous speaker in the chain. Also when you go parallel, if one speaker dies, the others continue to work; this is not true for series. The lower the impedance, the harder it will be for your amp to survive or perform the work. 4Ω or 8Ω loads will cost less to amplify. Amplifiers that run 1 or 2 ohms are expensive.

It is my opinion that parallel wiring sounds much better.

  • The ideal situation here would be, one speaker with one amplifier.
  • If you wire two of them in a parallel, you will drop the load from 4Ω to 2Ω.
  • If you wire two of them in series, you increse the load from 4Ω to 8Ω.
 

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I want to do parallel wiring but without dropping under 4ohms which the power amp cannot handle.
Can't happen. Wiring in series would result in an 8 Ohm load on the amplifier. What make and model amplifier is it?
 

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A cheap (come on, $110?) pro audio power amplifier which the manufacturer doesn't even provide complete information about is a sure recipe for failure. The name of this manufacturer would be enough to have me steer way clear of them. Get a decent pro audio power amp from Crown, QSC, etc. which can handle a 2 Ohm load and you will be able to do what you want.
 

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Discussion Starter #17
dude im 16 in high-school, no income, I need something cheap, I mean crown is great I know great brands and quality products but geez they cost an arm and a leg for them, basically im steering for low cost, decent quality
 

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A cheap (come on, $110?) pro audio power amplifier which the manufacturer doesn't even provide complete information about is a sure recipe for failure. The name of this manufacturer would be enough to have me steer way clear of them. Get a decent pro audio power amp from Crown, QSC, etc. which can handle a 2 Ohm load and you will be able to do what you want.
:TT

That amp is going to cause a fire if you decide to push more than 50 watts from it, especially if you do a low impedance load like we are talking here with car Subwoofers.

dude im 16 in high-school, no income, I need something cheap, I mean crown is great I know great brands and quality products but moowee they cost an arm and a leg for them, basically im steering for low cost, decent quality
Low Cost and Decent Quality on the scale we are talking are not possible if you want to by new equipment. Your best bet to search your local craigslist for Paradigm Subwoofer, some Paradigm Monitors Version 3 (Mini or Monitor 5). These speakers can typically be found used for $100 a pair (give or take). Cerwin-Vega home speakers are for sale on my local craigslist for under $100. A used stereo or surround receiver can be found on ebay or craigslist for under $100. I frequently find some decent Adcom stereo and multi-channel amplifiers on craigslist for $100-200 all week long. Great brands can be had on any budget, provided you are patient and know where to look.
 

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I dont want used equipment, thanks though :)
I've found some really nice stuff, barely touched by the previous owner in almost new condition. Kind of like a three year old car with a 1,000 miles and a low selling price. Unless you can come up with a reasonable budget, then I cant see it any other way. If you go with this really low quality stuff you are looking it, then I can almost promise its not going to last and will end up as landfill in a year or so. And chances are that amp cant provide enough current to drive a 4ohm subwoofer which will result in a blown speaker and burned amplifier.

A few months working weekends at McDonalds with all the money saved, will certainly buy you a nice $1,000 system for your car or home. As a teen, I used to mow lawns about 6-10 hrs a week and made over $500-600 a month (in yesteryear dollars). At the end of the summer, I had almost $1500 in my pocket.
 
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