On Tue, 23 Dec 2003 22:21:52 -0600, "Rusty Boudreaux"
wrote:

"Stewart Pinkerton" wrote in message
...
OTOH, your ceiling will rattle like crazy..........

If you use a manifold with opposing drivers it won't be any worse
than a box sub at the same SPL. Rattling, shaking, etc will be
solely from acoustic coupling.

Well, unless you have the box on springs, it will also be due to
mechanical coupling. IME, ceilings are not so strongly built as
floors!

Ultra-long throw 15" drivers such as the Stryke AV15 handle
overdrive quite well. Xmax is 23mm but Xsus is over 30mm. The
suspension is designed to handle overdrive without damage up to
the power rating of the coil. That said, once you hit Xsus
you'll never want to do it again...the aluminum voice coil former
hitting the backplate sounds like a shotgun blast.

Yup - that was my point. You can certainly do this with an IB, and I
doubt that it does the components much good! :-)

With four
drivers we're talking over 20 liters of displacement at Xsus.
For another $700 you can make it 40 liters. An amp with an 8 Hz
double integrated 3rd-order Butterworth high-pass filter will
essentially eliminate hitting Xsus.

Or you can just use the correct size of sealed box and avoid the
problem altogether........

above my listening room, but I'm going with a pair of Tempests in a
200 litre sealed box, driven by a 500 watt amp. This works
pretty

Four AV15's in an IB will give you 3x the output capability at
Xmax (15 liters vs 3 liters).

Unfortunately, I have to use what's available in the UK, which doesn't
include the Stryke AV15 - and I can't afford a pair of Tumults!
--

Stewart Pinkerton | Music is Art - Audio is Engineering