Brooks RM 909 Highs

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

Crossover, Passive
Used inside of full range speaker cabinets to separate highs, mids, and lows and send them to their respective speakers within the each cabinet. These are not as efficient as active crossovers because they require all frequencies to draw from the same source of amplification.

Brooks Hi Fi speakers Contact Microphone
A device that senses vibrations and puts out an audio signal proportional to the vibrations.

Isolation
A containing of the sound wave in a certain area so that it will not leak into other areas and/or unintended mics.

Brooks HI FI projectors Consumer Format (Consumer DIF)
A standard adopted by IEC for sending and receiving digital audio based on The AES Professional Interface.

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

Circuit
1) One complete path of electric current.
2) Similar to definition 1, but including all paths and components to accomplish one function in a device.

Cut-off Rate (Slope)
The number of dB that a filter reduces the signal for each octave its frequency past the filter's cut-off frequency (outside of the pass band).