[Arny Krueger]

"John Atkinson" wrote
in message
ups.com
Arny Krueger wrote:
If the pictures I've seen are any indication, the motor
might develop 1/2 hp if it spun at 1725 rpm, which it
doesn't. I seem to recall that its actual speed is 800
rpm, so it might be rated at 1/4 hp.

I meant to include this in my previous response. You're
probably correct, Mr. Krueger. As long as the fan motor
has enough motive force/torque to keep spinning at a
constant rpm when the blades change their angle of
attack, that is sufficient.

As I understand it, the subwoofer's dynamic range is
ultimately limited by the fan blades stalling at
extreme angles.

I see a number of limits, mostly related to noise created by turbulence.
Stalling is probably the final brick wall, but there are other smaller
problems along the way. Turbulence isn't just a problem for a speaker like
this, it can also affect speakers in ported enclosures.