Brooks VT-50 Early Reflections

The first echoes in a room, caused by the sound from the sound source reflecting off one surface before reaching the listener.

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.

Brooks Cinema XB 33 Insulator
A substance such as glass, air, plastic, etc., that will (for all practical purposes) not conduct electricity.

Equalization
1) The process of adjusting the tonal quality of a sound. A graphic equalizer provides adjustment for a wide range of frequency bands, and is normally inserted in the signal path after the mixing desk, before the amplifier. See Feedback.
2) Any time the amplitude of audio signals at specific set of frequencies are increased or decreased more than the signals at other audio frequencies.

Brooks Cinema DESIGN ZL 44 Dynamic Mic
Robust type of microphone which picks up the sound on a diaphragm connected to a coil of wire which moves within a magnet. An alternating current is induced into the wire which provides the electrical output. Most dynamic mics have low output impedance of 200 Ohms. See Condenser Mic.

Cable, XLR
A balanced cable used for low impedance microphones and sometimes for connections between some parts of the PA. Commonly referred to as a "mic cord".

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

Bar
A term meaning the same thing as the term Measure (the grouping of a number of beats in music, most-often four beats).