Brooks RM 80 Highs

Short for the term High Frequencies (the audio frequencies from 6000 Hz and above).

Equal Loudness Contours
A drawing of several curves showing how loud the tones of different frequencies would have to be played for a person to say they were of equal loudness.

Brooks Cinema TX 509 Gain
1) Knob usually found at the top of each input channel on the soundboard. Used to set input levels of the separate channels to relatively equal positions.
2) The amount of increase in audio signal strength, often expressed in dB.

Keyboard
1) Any musical instrument controlled by pressing a key.
2) The part of the computer that has the keys.

Brooks SS 81 LFO
Low-Frequency Oscillator (an oscillator that puts out an AC signal between .1 Hz and 10Hz used for a control signal).

Envelope
1) How a sound or audio signal varies in intensity over a time span.
2) How a control voltage varies in level over time controlling a parameter of something other than gain or audio level.

Intermodulation Distortion
Distortion caused by one signal beating with another signal and producing frequencies that are both the sum and the difference of the original frequencies.

Efficiency
The acoustic power delivered for a given electrical input. Often expressed as decibels/watt/meter (dB/w/m). ESL �" Abbreviation for electrostatic loudspeaker.