Distance between two points in the same position on a wave in two consecutive cycles (two cycles directly following one after the other). For instance, the wavelength could be measured by taking the horizontal distance from a point at the peak of the wave in one cycle and a point at the peak of the wave in the second cycle (distance between the tops of two wave cycles). w frequency sounds have long wavelengths while high frequency sounds have short wavelengths. The wavelength for a 20 Hz sound wave is 56 feet. For this reason, speaker drivers called on to produce low frequencies must be large in size with high excursions (the distance a speaker driver moves in and out) in order to produce such large waves. Conversely, speaker driver producing high frequency sounds must be small in order to move quickly enough to produce the tiny wavelengths found at high frequencies (about two thirds of an inch at 20 kHz).