8
1.0 Introduction
1.1 OMNIDRIVE TM
Compact
Loudspeaker
Management
System
Introduction
An arrangement of 3 inputs and 5 outputs, and an additional internal sum of
inputs A&B, can be matrixed in any combination to provide a complete
loudspeaker management system with integral crossovers, delays, EQ, and
protection limiters.
In stage monitor systems, the FDS-355 can function as a dual bi-amp crossover
with delay, limiters and EQ, providing a solution to on-stage hotspots caused
by monitors with identical signals, which can be eliminated by applying small
delays between wedges.
Furthermore, the FDS-355 can function as a distribution unit to multizone
systems where crossovers may be passive or local to the loudspeaker. In this
case, the provision of delays and EQ can radically enhance such a system,
while reducing both processing costs and required rack space.
The FDS-355 brings the power and usability of OMNIDRIVE into 1U of rack
space. It has new 24-bit A-D input converters giving further improvement in
dynamic range, together with the familiar OMNIDRIVE 20-bit D-A converters.
A new BSS technique has been used, which combines system software and
hardware to optimise the performance of the output converters. This ensures
that the D-A is always operating at full range, minimising converter noise
whatever the system operating level.
All the system operating software is held in flash EPROM, which means that
upgrading to new software is easy - either via PC card or from a PC via the
MIDI or RS-232 ports. 60 internal program locations are available to the user
for storing system setups, which may be generic system programs or complete
venue settings. These memories may be stored onto a PC card for backup or
archiving. The FDS-355 can also be configured as a fully secure unit, with
password protection at multiple levels to prevent unauthorised tampering.
Crossover slopes of 6,12, 18, 24 or 48dB per octave, filter types Butterworth,
Bessel or Linkwitz-Riley, as appropriate.
Output limiters on each band (mid-filter).
High resolution input and output delays up to 1.3 seconds in 11
microsecond steps.
Input LED metering, showing signals from -20dB to clip level.
Output LED metering, showing signals from -20dB to +6dB over limit
threshold.
Front panel output level trims and Mutes
Polarity reverse on each output.
Phase adjustment for each output.
PC card port for storage and recall of program settings
Electronically balanced inputs and outputs with transformer options.
MIDI and RS-232 ports on rear panel.
1.2 Other features
