jiggaman

what's the benefit of a dual voice coilover subwoofer?

elduderino

The main advantage is impedance flexibility as a way to get max power out of an amplifier. A single amp channel usually puts out maximum power into a 2 Ohm load, and shuts down or blows up with a load much below two ohms. A bridged-mono pair of channels (diffferent than a single mono channel) puts out maximum power into a 4 Ohm load, and shuts down or blows up not far below that.

So if you have 1 four-ohm woofer connected to a 5-channel amp's MONO channel, it won't develop max power - it is seeing 4 ohms, not 2. If you have a single woofer with two four-ohm VC's, you can connect them in parallel ((+)'s together, (-)'s together) and Ohms Law says you get 2 Ohms, and Max power. This is why many (most?) woofer makers make both 4 and 8 Ohm versions of their subs - to allow installers who can do math to get the most out of the amp without blowing it up.


If you take the above principle and apply it to amps that really do handle much lower impedances (often denoted "competition" amps based on the reason they were originally created) it still holds. I just didn't want someone to come along and complain that I didn't mention these.

A disadvantage is that you hav to fit 2 voice coils into the spave for one. That means that each VC is smaller than a single one would be, and there is a decrease in power handling per VC. Since most speakers are blown up by distortion and incorrect enclosures rather than too much power, that is not the biggest disadvantage in the world, but it is true.

Back in the stone age, when many amps weren't bridgeable, DVC woofs were a way to get a single woofer added into a stereo amp system. Not really needed any more.

jiggaman

i have a kicker 600 watt mono amp. would i benefit from a DVC subwoofer?

elduderino

It is a function of how many subs you are going to run, really... and what impedance your amp is stable down to. Which model amp is it? (that kind of info always helps).

You used the singular in describing the woofer. If you are only using one woofer, and you have a 600W RMS amp (into 4 ohms, which is the only spec worth worrying about), you don't need DVC (IMHO). I'd take the greater power handling of a SVC. Let's assume you have a mono amp that is 600W into 4 ohms. If it's 1200 watts into 2 ohms, great - do you need that much? Probably not.

But if you have a 300W amp into 4 ohms and it's only 600 into 2 ohms, it's a bit less obvious... but again, I'd probably go SVC. I'm a big fan of using impedance as a way to get max power out of smaller amps when on a budget - but when you have a 300 watt amp, I am not that worried about it.

(Now I will get flamed by someone who looooves DVC woofers).

All that is only assuming a single woofer.

jiggaman

here's my amps stats, and i'm running two 12s with it.

Amplifier Type: Mono
RMS Power: 300W x 1 @ 4 ohms
THD at 4-Ohm RMS Power: n/a
RMS Power: 600W x 1 @ 2 ohms
Speaker Level Inputs: No
Preamp Outputs: Yes
Built-In Crossovers: LP
Bass Boost: 0 - 18 dB
Frequency Response: 20-200 Hz
Signal to Noise Ratio: >95 dB
Fuse Rating: n/a

elduderino

If you are running 2 4-ohm 12"s right now, you are hopefully wired to a 2-ohm load, and your amp is developing 600W into 2 ohms.

If you replaced your 2 12"s with 2 DVC 12"s with 4-ohm VC's, you would either:

A) have to wire them to a 1-ohm load, shutting down or blowing up your amp,

or

B) wire them for a load higher than the 2 ohms you have now (4 or 16), causing your amp do develop LESS power. (All the DVC woofers I have seen for years are 4 ohm VC's)

So, if you are looking to run 2 12"s with your amplifier, 4 Ohm DVC woofers are actually WORSE for you.

P.S. If you are using 8-ohm woofers right now, are are only developing 300W, not 600W. You might want to replace them with two 4-ohm SVC woofers, for a total 2-ohm load, and 600W.

jiggaman

thanks for all your help