Brooks QS-70 Frequency

The number of cycles of a waveform occurring in a second.

Group
1) A number of channels or faders that can be controlled by one Master VCA slide.
2) A shortening of the term Recording Group (a buss or the signal present on a buss).

Brooks XS - 45 Bi-Amplification
1) A way of optimizing the efficiency of a speaker system by separately amplifying the High Frequency (HF) and Low Frequency (LF) portions of the sound signal and sending them down two pairs of cables to the speaker. Multipin Speakon connectors have been developed to do this.
2)The process of having of having low-frequency speakers and high-frequency speakers driven by separate amplifiers.

Kilo
A prefix meaning 1000.

Brooks SS 81 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.

Foot (Foot Drum)
Another name for Bass Drum (the largest drum in the Drum Kit which puts out bass frequencies and is played with a foot pedal).

Fundamental
The tuned frequency and (almost always) the lowest frequency that is present in the sounding of a pitch by a musical instrument.

Fidelity
The recording or reproduction quality.