Glossary of Terms

2-way speaker : A 2-way speaker has two drivers, a tweeter to handle high frequencies, and a woofer to handle mid to low frequencies.

Background music : Music that is intended to provide an unobtrusive ambient atmosphere to a location.

Crossover : A circuit that divides the frequency spectrum into two or more parts. A crossover acts as a filter, allowing certain frequencies to pass through to the speaker while blocking others, sending only high frequencies to the tweeter and only low frequencies to the woofer.

Decibel (dB) : a unit used to measure the intensity of a sound or the power level of an electrical signal by comparing it with a given level on a logarithmic scale.

Dispersion : The degree of which a speaker’s sound is spread over the listening area.

Driver : Any individual device on a loudspeaker that contributes to the creation of sound, also referred to as woofer or tweeter.

Dynamic range : the ratio between the largest and smallest possible values of sound.

Frequency response : Measured in Hertz (Hz). The human ear responds to frequencies from 20Hz to 20kHz (approx). A speaker’s frequency response indicates how much of that range can be reproduced.

Hertz (Hz) : A unit used to measure sound frequency.

Impedance : The amount of resistance to the ow of current, measured in Ohms.

In-ceiling/In-wall speakers : Speakers that have been specifically designed for installation in a ceiling or wall to mount flush. The cavity in the ceiling or wall acts as a cabinet, so the speakers can produce more bass compared to standalone speakers.

Neodymium : A material used in some speaker magnets. Neodymium magnets are smaller and more powerful than conventional speaker magnets.

Ohms : The measurement of electrical resistance. Often used to show the impedance of a speaker coil.

Outdoor speakers : Speakers that are designed specifically for placement in outdoor environments. Many outdoor speakers are designed to project sound over a larger area and to provide a little more bass than typical indoor speakers. They are also built to be weather resistant.


RMS : A term used to indicate the average level of power that a receiver or amplifier can sustain over a given period of time. Average power ratings provide a more realistic assessment of your amplifier's performance than peak power since an amplifier can only sustain peak power for a short period of time. RMS stands for “root mean square”, which is one of the mathematical methods used to calculate an amplifier's average power output. While it isn’t an accurate descriptor of the measurements themselves, it’s commonly used throughout the industry to denote the average power rating.

Satellite speaker : Small speakers generally used as surround speakers placed or mounted in various locations (hence the name “satellite”) around a room for a home theatre setup. Because they tend to have limited bass response, they’re often designed to be used with a matching subwoofer.

Sensitivity : Sensitivity ratings shows how effectively a speaker converts power (watts) into volume (decibels). The higher the rating, the louder your speakers will play with a given amount of amplifier power. Sensitivity is often measured by driving a speaker with 1W and measuring the loudness in decibels at 1m and described as SPL (sound pressure level).


Subwoofer : A speaker specially designed to reproduce a range of very low frequencies only (the bass). The typical range for a subwoofer is about 20-200Hz. A “powered subwoofer” includes a built-in amplifier to drive the speaker.

Tappings : 100V line speakers can have multiple power settings. For example: 20W, 10W, 5W, 2.5W

Terminals : Spring clip terminals work best with bare wire connections with small-gauge speaker wire, or pin-type connectors. Binding post terminals are a sturdier, more versatile type of speaker jack, often found on higher-quality speakers and receivers, and on most amplifiers. They are threaded, so you can tighten them down against the wire or connector for a tight connection.

Transient : A short-lived aspect of a signal, such as the attack and decay of musical tones. A speaker that can react quickly to rapid changes in the music is said to have good “transient response.”

Tweeter : A small, lightweight driver that reproduces the highest musical frequencies, like violins, cymbals, female vocals, etc. The typical range for a tweeter is everything above 2,000Hz approx.


Watt : A unit of power. Equal to the power in a circuit in which a current of one ampere flows across a potential difference of one volt.

Woofer : A type of driver that features a cone-shaped diaphragm, commonly used for producing the mid and low frequency portions of the music signal.

Credit to one of our suppliers - AVSL - for this useful glossary of terms.