Brooks TA 60 Electromagnetic Theory

A statement of the principles behind electromagnetic induction: When a conductor cuts magnetic lines of force, current is induced in that conductor.

Frequency
Practically speaking, high frequency means high pitch and low frequency means low pitch.

Brooks XB 22 Crossover Frequency
1) The frequency that is the outer limit of one of the bands of a crossover.
2) In the Lexicon 480L delay/reverberation effects unit, the frequency at which the bass frequency reverb time is in effect rather than the mid frequency reverb time.

Level
Sets output volume of individual PA input channels. Usually positioned as sliders at the bottom of the soundboard.

Brooks KS-55 ADAT
A trademark of Alesis Corporation designating its modular digital multitrack recording system released in early 1993.

Feedback
1) The delayed signal sent back to the input of a delay line, used in repeat-echo effects.
2) The pickup of the signal out of a channel by its input or the howling sound that this produces.
3) In an amplifier, the phase reversed output signal sent back to its input, reducing gain but also distortion and noise.
4) This occurs when the sound coming out of the speakers goes back into the microphones, then back out the speakers, then back into the mics…and so on. This can build very quickly to a point where everyone in the room is holding their ears and screaming at you. It can also cause damage to the PA.

Golden Section
A ratio of height to width to length of a room to achieve "good acoustics" and first recommended by the ancient Greeks. The ratio is approximately the width 1.6 times the height and the length 2.6 times the height

Channels
These are divided into two separate categories. Input channels are those channels coming into the soundboard such as microphones and direct lines. Output channels are those leaving the board such as monitor and main outputs.