Single Vs. Dual Sub

[Tomorrow]

Hey good people.

Please educate me, cuz I sure don't understand the dynamics involved. What would you expect, spl and sound quality-wise, from a sealed, single driver 300W powered sub, vs. a sealed, dual sub, powered by a 200W amp, all other things being equal (size, hardware, amp specs other than wattage, cabinet bracing, speaker material, manufacturer, etc.)?

Thanks in advance for your time.

RJ

 

[warnerwh]

Well there's the quality of the drivers themselves. Also two woofers instead of one woofer, all else being equal, will put out 3db more sound with the same amplifier input. It takes double the power to get 3db more output: 100 watts into the same speaker is only 3db louder than 50 watts. You should delve more deeply into the subject if you're considering a purchase because there's alot more to it than what you're asking and there's some very good deals in subs to be had. All 10" subs aren't the same and that's one reason one costs 300 and another a 1000. There's many 10" subs that will outperform many 12" subs.

 

[Tomorrow]

Thanks, Warner.

I know there is much to study re subs. But my question is very specific regarding the benefit/trade-off of single vs. dual subs. It's a theoretical application I'm interested in. As an example, take an Hsu VTF-3 and make a dual out of it (with obvious changes in cabinetry, etc.), but reduce the amp power by 1/3. What, then, is the net effect on spl and sound quality?

 

[slopoke]

Many varibles here.

The major problem is that it depends on the amp and the driver, neither of which you know enough about to make a general statement.

For example, in a perfect world if you halve the load on an amp (8ohm->4ohm = 2x8ohm drivers in parallel) it should double the power output yielding a 3db gain. In reality most class A/B amps only get a power increase of 1.6. If its a digital amp then the whole thing could be different.

If you take the above situation and make the drivers 4ohm ones instead of 8ohm then the combined load goes to 2ohms. Can the amp handle a 2ohm load? Or you could wire the drivers in series to make it an 8ohm load making the 200 watt amp look more like 100 watts.

You see the problem here. You need to know all the specs on the amps and the drivers involved as well as how you plan to connect them in order to make a guess. Problem is sub manufacturers don't ususally give you these specs because in normal usage it doesn't matter, they've done this design work for you.

And all the above assumes a "perfect" cabinet and doesn't even mention that cabinet geometry can affect the phase relationship of the dual drivers throwing in yet another variable.