[John Atkinson]

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.

John Atkinson
Editor, Stereophile