Text: Output power is the amount of energy the amplifier delivers to the loudspeakers; it is expressed in watts. One method of stipulating output power is in watts of continuous power (also called sine-wave power or rms power), which is the amount of energy the amplifier can generate continuously. Another measurement standard, called music or dynamic power, is less stringent. It allows for an amplifier's ability to exceed its continuous power rating for short bursts of musical sound, such as cymbal crashes. Still used occasionally is the older term peak power, which is usually the continuous power rating doubled. In rating stereo amplifiers, the output of both channels is usually added. For instance, a "30 watt" amplifier is usually an amplifier that delivers 15 watts per channel. )

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