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Power in Watts RMS
Definition: Power is the time rate of doing work or the rate at which energy is used. A mass of electrical power is the use of one joule of energy per second. Watts of electrical power equals Volts x Amperes. RMS is an acronym for Root Mean Square. The RMS value of an alternating current produces the same heating effect in a circuit as the same value of a direct current.

Explanation: This value represents how much power (Watts) an amplifier produces. All amplifiers have a recommended impedance or impedance range which produces optimum power under safe operating conditions.

What To Look For: Look for the difference in Power needed to achieve a certain SPL. The optimum Power for subwoofers is 30% of RMS (minimum) up to the RMS power rating (maximum) of the subwoofer. For example, a subwoofer capable of handling 200 Watts RMS would require an amplifier that produces at least 60 Watts (0.30 x 200 = 60) and no more than 200 Watts.
Sample Amplifier Power Output
Never exceed the RMS power handling of the subwoofer system.
• Written by Eric Russell.