Brooks RM 909 Line Out (Output, Send)

Where a signal leaves the board or component.

Keying Input (Key Input)
An input on a dynamics processing device to control the device by an external audio signal.

Brooks HI FI projectors Headroom
1) The level difference (in dB) between normal operating level and clipping level in an amplifier or audio device.
2) A similar level difference between normal tape operating level and the level where the distortion would be 3%.
3) The difference, in decibels, between the peak and RMS levels in program material.

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

Brooks Hi Fi reviews In Port
A jack on a MIDI device or computer that will accept an incoming data signal.

Harmonic Distortion
The presence of harmonics in the output signal of a device which were not present in the input signal.

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

Hard Disk (Hard Disc)
A storage unit for digital data that has rigid disks coated with magnetic material in a housing that includes the drive mechanism.