[Anechoic]

A wavelength of 3 meters is about 100 MHz in the RF world, and 1 kHz in audio terms.

An acoustic wavelength at STP is around 1ft/30cm, not 3m (which is closer to 100 Hz).

[CamperBob2]

D'oh, you're right; I started punching calculator buttons with 1100 f/s and turned it into meters somehow.

Point stands, though.