ARCHITECT'S AND ENGINEER'S SPECIFICATIONS
FDS-334T/336T MINIDRIVE Loudspeaker Management Systems
The Digital Crossover System shall be configurable from a combination of two inputs and six (four) outputs, in a single 1U rack-mounting unit, each output having facilities for crossover, parametric EQ, mid-filter limiters, and delays. Each input must have facilities for parametric EQ and delays. Any output may take its feed from any input, including a mono sum of the two inputs. All functions must be accessible through front-panel switches, including independent and directly accessible MUTE buttons and LEVEL TRIM controls for each output.
The unit shall have electronically balanced analogue inputs and outputs.
All data shall be displayed numerically to provide a visual reference of crossover points, delay times, limiter and EQ settings.
Individual LED meters shall be provided on each input and output. These LED indicators shall also show when clipping levels are approached. The input meters shall indicate signal levels of SIG (-20dBu), -3dBu, 0dBu, +3dBu, +6dBu, +12dBu and CLIP (+18dBu). The Output meters shall show levels relative to the limiter threshold of SIG, -20dB, -12dB, -6dB, -3dB, 0 (Limit Threshold) and OVER (signal 6dB over threshold level). The LED meters must at all times show the output signal level, regardless of MUTE condition.
Each crossover output band shall be selectable to operate with a slope of 6, 12, 18, 24, 36, 48 or 52dB per octave. The filter types available shall be Butterworth, Bessel, Linkwitz-Riley or WHISEWORKS - NTM, dependent upon slope selected. Each band shall have polarity inversion switching . Each band shall be adjustable for both high and low-frequency roll-off points, individually or in crossover pairs.
Each input and output shall have freely assignable parametric EQ, each EQ section having a centre-frequency range of 15Hz to 16kHz, with adjustable gain of +/-15dB in 0.5dB steps, and a variable Bandwidth (selectivity) adjustment of 0.05 to 3.00 octaves in 0.05 octave steps. The filter shape shall be selectable between bell or shelving, with selectable shelving slopes of 6dB or 12dB per octave, low or high shelf characteristics.
Each output shall have threshold adjustable mid-filter limiters, with threshold adjustment of -10dBu to +20dBu.
Each input and output shall have a delay line, adjustable up to 635 milliseconds in 21 microsecond steps. Delay settings should be set and viewed in milliseconds, feet, metres or frames-per-second (24, 25 or 30 fps). It shall be possible to link bands for relative delays.
There shall be no less than 60 memories for the storage of system data. It shall also be possible to output memories via MIDI to a MIDI storage device.
Password protection shall optionally disable the setting and viewing of parameters by non-authorised personnel.
There shall be provision for remote control via MIDI or RS-232, and it must be possible to update system software via MIDI or RS-232. Units must be able to pass data to other similar units using MIDI transfer.
The Digital Crossover System shall be the BSS Audio FDS-336T (FDS-334T) MINIDRIVE.