2 subs vs. 1

[darin]

I am in the process of purchasing a jmlabs sib & cub system. (6 sibs) The sub that comes with the system is only 75 watts with a down firing 9" driver. I have the opportunity to get 2 of these subs OR the Chorus SW700 S sub which is a 300 watt front firing 11". Would the 2 subs work better?...They are definitely smaller and better fitting in the room. Any concerns with bass cancellation?...What will give me the most pounding volume?

[Ken L]

this isn't really my cup of tea _grin_

But since no one else has posted to this thread, I'll give you some input -

caveat - there's all sorts of info not available in this thread

IMHO, watts quoted by manufacturers of such items is usually next to meaningless,

As a former bass player for a number of years, long time ago.

I would unhesitatingly go for a 11" over two 9"s if all other factors are equal although theoretically they should be about the same

and that's a pretty big "if"

However, I would generally go with one heavier piece of equipment than two lighter/smaller pieces -

I also as personal preference would take forward firing over down firing generally speaking

regards

Ken L

[michael]

to be honest when it comes to buying commertial products the best thing to do is demo them, manufacturers specs are dubious andthey sometimes include average room gainwhen they give you the f10 response of 25Hz to 200Hz as an example, diy spec are more reliable. so i say goin the store and say i want either 2 of those 9"ers or 1 11" and get them to set that up for you.
from the info you gave there id say the11" just because of the size, it will probly have longer xmax and higher power and it will have larger sd, an likely lower response, resulting in better deep bass and 1 enclosur is easier to place without problems

[planet10]

Buy subs? What a novel concept... i'm sure for what any of those subs cost you could build a pair of push-push subs with decent plate amps... and have some change left.

dave

[The Paulinator]

I REALLY recommend getting two subs and place them at different sides of the room. This really helps to nullify standing waves and will make things sound alot more even. And, although people are iffy about this, I really recommend using subs below each speaker in a stereo setup, running in stereo. THere are things that won't sound the way they were supposed to unless you have stereo subwoofers.

[CZ Eddie]

Originally posted by The Paulinator
I REALLY recommend getting two subs and place them at different sides of the room. This really helps to nullify standing waves and will make things sound alot more even. And, although people are iffy about this, I really recommend using subs below each speaker in a stereo setup, running in stereo. THere are things that won't sound the way they were supposed to unless you have stereo subwoofers.

I thought most receivers put out the LFE in mono, so no stereo is really possible?

I could be wrong though.

[kelticwizard]

The two 9" subs probably have a cone area slightly greater than the 11 incher. However, However, since excursion tends to get greater the larger the diameter of the sub, (it doesn't have to be that way, but usually that is how it works out), I would guess the 11 incher probably can move a little more air-which means produce a little more bass.

Two subs, at equal volume, will sound 6 dB louder than one sub at the same power. It takes four times the power to raise a single sub 6 dB. However, the 11 incher, at 300 watts, has four times the power of the 9" subs powered by 75 watts.

Statistically, it is a standoff between the two 9s and the single 11.

However, my guess is that the 11 incher is probably built to go deeper, and is probably a better sub. 75 watts and an 8 inch sub says to me that the manufacturer really didn't have very high goals for his sub in terms of bass output. While 11 inches and a hefty 300 watts tells me the manufacturer at least intended intended to produce a fine sub.

Best thing-audition. If going in cold-buy the 11 incher.

Really the best thing-build your own.

[planet10]

Originally posted by CZ Eddie
I thought most receivers put out the LFE in mono, so no stereo is really possible?

Redirect the LFE to the L&R mains which each have a sub attached to them.

dave

[KevinLee]

Two 9" subs has 25% more cone are than one 11" sub.

Comparing cone areas is easy, comparing the power ratings between the two is not.

I would try both set-ups in your room.

If these subs have high level input, you could have stereo bass if you use the (2) 9".

Regards

KevinLee

[av_phile]

I personally prefer two subs in a stereo set-up. In an HT or multi-channel sudio set-up, another pair at the back.

It is common notion to consider bass frequencies as non-directional so one finds many receiver giving out mono LFE. Non-directionality is true only if the sub's crossover starts at around 60 hz. Above that, directionlaity becomes apparent. One needs only to listen to a headphone to distinguish between bass that is mono and one that is in stereo. One can still identify a kick drum or a viola/piano's lowest notes coming from either a left or right speaker. Summing their 80-100 hz together into a mono signal losses much of the stereophonic soundstaging.

While it is possible that two bass sources may cancel each other out in a room where speaker placement is critical, it is also possible to get smoother and more uniform bass dispersion with multi sub placement. I have expereinced using only one sub and there are room nodes where the bass is stronger while in other areas, there's hardly any. Putting another idnetical sub in another location solved the uneveness nicely.

Bass frequncies are best reproduced in general with the largest cone area possible in order to displace as much air volume as possible. (Ofcourse recent designs with more pliant and long throw 8" woofers can also do the jub.) So between a single 11" and a double 9" I'd go for the latter, with all other asoects equal. The latter's cone area is effectively 18" together. Also, having two woofers doubles the "engine" of the speaker. (Vandersteen uses three downfiring 8" woofers in its subs)

But in this particualr case where the 11" sub uses a 300 watt amplifer versus a couple of 9" subs using 75 watt amps each, I'd chooce the former as it should give more slam due to its higher amplifier rating. Better still if you use two of these. Just my 2 cents.