Speaker Specifications

What do these specifications mean?

FREQUENCY RESPONSE
Frequency response is the range of frequencies that a speaker can reproduce. 20 thru 20,000 Hz is the range of human hearing. Most good, full-range speakers will be rated at 20Hz-20KHz. Most often an additional specification, the “variance” (i.e. ± 3dB or ± 6dB) is included in the specifications. In general, a smaller amount of variation indicates better, more reliable response over the specified frequency range.

IMPEDANCE
Also referred to as electrical resistance, impedance is the electrical characteristic of a speaker that inhibits the flow of power from your receiver or amplifier. Measured in “ohms”, impedance describes how difficult a speaker is to "drive," and thus indicates its compatibility with various amplifiers. Most home stereo speakers are designed to present 8 ohms of resistance. If you are considering speakers with less than 8 ohms impedance, you must be certain that the amplifier you intend to use is compatible with a low-impedance speaker.

POWER HANDLING
Peak (MAX) Power-handling Capacity: This term refers to the maximum amount of power a speaker can handle in brief, high-intensity bursts. Since this can vary with frequency and amplitude, this measurement is not a very accurate gauge of speaker performance.

RMS (Root Mean Square) Power-handling capacity: RMS is a formula that provides a reasonably accurate method of measuring and comparing continuous power. It computes a speaker's ability to handle a steady flow of power on a continuous basis. RMS capacity is usually slightly more than half of the maximum, or peak capacity. (for more information refer to: RMS Power vs. Peak Power)

Minimum recommended power: This specification denotes the minimum amount of power needed to drive the speaker. To illustrate, operating a speaker with a 40-watt minimum using an amplifier that only supplies 40 watts, would result in forcing the amplifier to operate at the limits of its capacity, resulting in distortion in the audio signal, and possibly causing damage to the amplifier or speaker.

SENSITIVITY
Also known as "efficiency", sensitivity refers to how efficiently the speaker converts the power from the amplifier into sound. It indicates how loud (in decibels) the speaker sounds at a distance of one meter when it receives one watt of input power. Generally the specification looks like this: 90dB @ one meter. A speaker with a higher number would convert power into sound more efficiently than a speaker with a lower number. Since a speaker with higher sensitivity requires less power to play just as loudly as a low-sensitivity speaker, resulting in less distortion of the sound, this can be an indicator of how good the speaker sounds when you “pump up the volume”.