Acoustitape

The Genelec Acoustitape is 3 metres long, covering frequencies down to 115Hz. It shows the time periodicity for each frequency as well as how far sound travels over a given period.

Next to each frequency on the tape is a bold-printed quarter wavelength frequency. The purpose of the bolded quarter wavelength frequency is to help you understand where the predicted dip in the frequency of a loudspeaker will be when placed at a certain distance from the wall behind it. Bass waves are omnidirectional in nature, and if they meet the wall behind the loudspeaker at the quarter wavelength, they will bounce off the wall and return to the loudspeaker tens of milliseconds later only to be 180 degrees out of phase with the direct sound, causing a cancellation. (¼ +¼ = ½ or 180 degrees out of phase).

Printed on the reverse side is a standard measuring tape in inches and centimetres.