18" bass cab....or just more smaller drivers?

Oh good, you're the person we need to buy the Bergantino HT-118 and let us know how it sounds!

Nightbass

 

No, an informent

The Bagend 18 seems to handle low's pretty well but I have no Idea about the Eden.

 

It's not totally clear to me what you're after. If you want to move a lot of air, in general the most efficient way to do it is with bigger drivers. But bigger drivers need bigger cabinets. You can get smaller drivers that are flat down to 30 Hz., but you have to feed them huge amounts of power to get appreciable output, and their cone excursions tend to be exuberant at the extreme low frequencies - and they don't tend to "throw" the sound out to the audience as well as their bigger counterparts. If you need a lot of fundamental out in the audience, you probably will need bigger speakers. I'm sure Eden's 1x18 is nice, but even it may have some shortcomings down at 30 Hz. There aren't a lot of cabinets out there that are capable of a big output down there. I have an Eden 2x15, which specs out at least as well as the 1x18, but its output is down a bit at 30 Hz. It is certainly acceptable to me, but I don't require absolutely flat response - and I rarely go down to low B anyway.

If you are willing to haul big subwoofers and power amps, then find an amp-subwoofer combination that will put out the volume you need at 30 Hz. If not, then you'll have to decide what you're willing to sacrifice - volume or low end.
- Mike

 

I should add that there is a technology that may be able to provide extremely deep bass in some venues without having to haul around huge speaker cabinets. See http://www.thebuttkicker.com/ for an example of this. It works like a vibration shaker table (used to test products for vibration failures), but couples into a floor or building structure to shake the daylights out of it. In essence, it turns a floor into a woofer diaphragm. This is akin to an early wise-cracking post of mine (in another thread) about placing a V-8 engine with an unbalanced flywheel on the stage. But seriously, this could provide an answer - particularly for a fixed set-up. On the other hand, if you are going from venue to venue, its performance might be very unpredictable. And you'd need a separate huge amp to drive it. And I wouldn't be surprised that it might actually do some damage in some marginal cases (e.g., cause plaster to fall or something). That's all I know about this or similar products at the moment.
- Mike

 

The Bag End 18" cabs are -6 dB at 36 Hz and really aren't much for a true subwoofer. The B-52 bandpass cabs are -3 dB at 30 Hz. They are very specialized, so I'd want to audition one before buying. Flite claims 32 Hz for their cabs, but IMO that is utter bullsh*t. Flite isn't willing to substantiate their claims of their cabs going so much lower than ALL the competition. He must have a special waver to violate the laws of physics...

I have not come up with a solution other than using true subwoofers, a huge amp, and bi-amping to get lots of bottom. One of my Rockford 15" subs move the same amount of air as 2.7 Rockford 10" subs. Also, my 15s go substantially lower than do my 10s. I run a pair of 1x15 Rockfords.

On paper, the 2x10 can be mounted in a 3 cubic foot extended bass shelf alignment which will give a nice peak right at 31 Hz. Even though it doesn't move as much air, the 2x10 with mutual coupling calculates at 91 dB compared to 87 dB of the 1x15.

The problem with the 2x10 design is the huge port area required to keep velocity below 5% MACH. The large port requires a very long duct, on the order of 60 inches, and that eats up cabinet space. The alternative is a pair of 12" passive radiators, but I haven't gotten that far yet.

 

If you want better lows go for a home stereo subwoffer kinda thing, a friend of mine that plays "latino dub" uses customized cabs loaded with different woofers I'll check with him and see what kind. You wouldn't beleive the lows he gets punchy and smooth at the same time, very cool.

 

The minimum area of the port is a direct function of the amount of volume displaced by the driver. A large port area avoids whistling and chuffing noises by keeping the port air velocity below 5% the speed of sound. The 10" mentioned above requires a smaller port area than the 15" does, because it only moves 37% as much air as the 15". The port area doubles when two drivers are installed in the same cabinet, such as a 2x10.

The port length (duct) is a direct function between the port area and the internal cabinet volume. Increasing the port area raises the port tuning frequency. Increasing the duct length lowers the port tuning frequency. The problem comes when using a large port in a small cabinet. A very long duct is required to tune a large port in a small cabinet. The long duct eats up internal cabinet volume and makes the net cabinet volume even smaller. This in turn makes the required duct length even longer.

My EBS design-in-progress for my 2x10 cabinet is almost as large as the 1x15, due to the port size problem. The 1x15 still moves more air, goes down lower, and costs less. The only compact 10" solution I've come up with so far is using two 12" rear-firing passive radiators as a substitute for big ports in small cabinets. PRs are typically sized higher than their driver to avoid over excursion. The downside is more expense, and mandatory vertical mounting. PRs can never fire up or down.. only horizontal due to the huge mass of their cones.

The ELF is the smallest, deepest and probably the easiest subwoofer solution I've seen. And very expensive. Put your wallet on the counter, and the sales guy will give you back the leather part, and keep everything else..

 

Bgavin, will the port still operate normaly if it is outside the cab? If so could you use some pvc or plastistic tubing that was "rolled" like a screw. I was thinking about that one day when I figured out there was not enough room for the port in a cab. It would be basically a "tailpipe" or a "stak" and you could move it where you wanted. just an idea.