Actually, MarkPhD is correct, except that in air, the speed of sound equals the wavelength times frequency. Also, even though your room will not support even one full 20 Hz wavelength, this is not the only factor in bass. Ever hear a boombox in a car and the low frequencies, not withstanding the hideous bass resonances and distortion? The reason is that subwoofers will pressurize and depressurize the air in the room at low frequencies. I have a JL Audio F113 subwoofer that has a calibration curve that runs from 20 Hz up to 150 Hz. A 20 Hz signal at pants-flapping levels is truly something to be experienced. A good treatise on bass is given at www.rotarywoofer.com. Supposedly this thing will go down close to 0 Hz.