Octave - In audio, the interval between any two frequencies having a ratio of 2 to 1. One octave up from 100 Hz is 200 Hz, where one octave down from 100 Hz is 50 Hz.

Ohm - The unit of electric resistance and impedance. One ohm is the resistance value through which one volt will maintain a current of one ampere.

Ohm's Law - E = I x R, where E is voltage, I is current, and R is resistance. This illustrates that more voltage will produce more current if resistance stays the same, but higher resistance will cause current to decrease if voltage stays the same.

Omni directional - Generating sound in all directions.

Oversampling - A technique where each sample from a data converter is sampled more than once. This multiplication of samples permits digital filtering of the signal, thus reducing the need for sharp analog filters to control unwanted frequencies created when sampling rates (see chart).