PMPO is short for Peak Music Power Output and is a specification found on many home audio systems, car stereos and portable speakers. It is a measure of the maximum power output of an amplifier or speaker and is usually expressed in watts.
As peak music power output is a measure of maximum power, it is not representative of the average power that an amplifier or speaker can produce. Consequently, PMPO should not be confused with RMS (Root Mean Square), which is a better indication of an amplifier or speaker's true power handling ability.
While PMPO numbers can be impressive, they are often meaningless as manufacturers often exaggerate their figures. As such, it is always best to look at other factors when choosing an audio system, such as build quality, features and reviews from credible sources.