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Sub-Amp Wiring Question - Damping Factor Vs. Power Vs. Bridged/Stereo Mode

I have a subwoofer with dual voice coils rated for 600 W. It can be wired to 2 ohm or 8 ohm. I have a two channel amp that can be bridged. Here are my wiring options:

1) 2 ohm subwoofer wiring on one channel of the amp which in this case provides 1,000 watts RMS

2) 8 ohm subwoofer wiring with bridged mode on the amp which provides 1,300 watts RMS. (The amp isn’t stable at 2 ohm bridged by the way)

As you can see, either mode provides ample wattage. More watts is usually better but there are other factors at play. One channel at 2 ohms provides a lower damping factor than the bridged option (I believe an 8 ohm load on the bridged amp would make the amp see a 4 ohm load which should provide a better damping factor. That being said, it seems to be the general consensus around here that bridged mode operation of amps doesn’t sound as good as just using one channel). 
 

So it really comes down to:

1) Less power, lower damping factor, non-bridge mode.

2) More power, higher damping factor, bridged mode.

 

Does anyone know what would provide better sound quality?

128x128mkgus

Showing 3 responses by oldhvymec

oldhvymec
5,101 posts
 

You can run Mcintosh valve amps in series or parallel. Normally one after the other they can't handle low impedance. Paralleled they can half the impedance, to 2 ohms. They sound like crap, but you can do it and that is what Mcintosh recomends..

Using a 4 ohm tap on a SS will give you the highest output with the least amount of dampening and cone control. The lower the impedance the higher the distortion and much lower if any dampening. IF they are using a passive XO only ONE type offers any dampening at all. 6db first order, BUT I guarantee when the impedance goes HIGH the speakers will go out of phase. 

Plate amps and Active XOs DON'T.. 

As I said 8 ohms offers better cone control and can offer a lower octave without a strain. It's a sub it dosn't need watts it just needs controlled movement. Nothing else to compete with so to speak.. WHY a million watts?

I could do it with 100 watt plate amps with cone control.. BUT 1000 watts will blow stuff up if it's not controlled some how.. Just saying.. :-)

oldhvymec
5,101 posts
 

8 ohms will give you a lot better dampening. I'd doubt if there is any at all at 2 ohms and the distortion is off the chart too. I wouldn't bridge anything and I would direct couple the drivers to the amp if that is what your trying to do. Get rid of the passive XO and use an active crossover. Your questions and problems are solved. You have the best cone control you can have and you won't burn the amp or the voice coils up because you overheated everything..

Unstable means unstable. Not knowing the sensitivity of the drivers is an issure too. I use 92% efficient 10" high excursion DVC drivers too. Dayton HO44-10. I can hit 10hz with a 12" passive. The question is do I need to? The screws back out of sheetrock doing that.

Regards

oldhvymec
5,101 posts
 

I use 12K Behringers on 91% efficient speakers @ 8 ohms. BUT I have a TON of overhead. I see the price doubled too. I use to get 3 for 1200.00 Great deals..
I'll tell you something else, they are dead quiet. They have fans, I disconnect 2 and put one on a toggle.. LOL Never even get warm, without a fan..6 years old now. They run 12 8" drivers or 4 18" HE drivers right up a flag pole.

82.7 mercy!!! 90-91% efficient is what I run. 82.7 you would need a welding machine to pump it out.

Start there 83% efficient is a tosser for me. Get a better driver, FIRST. 375 watts at 8 ohms on any of my systems will run you right out of the room. 110-115db. I can turn it all the way up to 100% 700 watts per sub (close) and hit 125 db, I can bump the gain, quit a bit. That is under 35% gain . High power class Ds and High efficiency speakers will get really loud, IF that is what you like. Direct coupled great dampening, otherwise VERY little.

Have a half way safe New year and the other half, don't be unsafe. BUT if you're gonna do something with the stereo while you're drunk, please take a video.. 

Half Safe, ALL the way HAPPY NEW YEAR.... Video Please.. :-)

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