BSS Audio FDS 355 User manual
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FDS 355
User Manual
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V 2.0 JMK 13th October 1997
Software version 1.10 and above
We have written this manual with the aim of helping installers and sound engineers to get to grips with the
FDS-355 and obtain its maximum capability. If you are new to BSS products, we recommend that you begin at
the start of the manual.
We welcome any comments or questions regarding the FDS-355 or other BSS products, and you may contact us
at the address or World Wide Web site given in the warranty section.
This equipment has been tested and found to comply with the following European and international Standards
for Electromagnetic Compatibility and Electrical Safety:
Radiated Emissions (EU): EN55013 (1990) Associated Equipment
RF Immunity (EU): EN50082/1 (1992) RF Immunity, Fast Transients ESD
Mains Disturbance (EU): EN61000/3/2 (1995)
Electrical Safety (EU): EN60065 (1993)
Radiated Emissions (USA): FCC part 15 Class B
Electrical Safety (USA): UL813/ETL (1996) Commercial Audio Equipment
Electrical Safety (CAN): UL813/ETLc (1996) Commercial Audio Equipment
IMPORTANT SAFETY INFORMATION
DO NOT REMOVE COVERS. NO USER SERVICABLE PARTS INSIDE, REFER SERVICING TO QUALIFIED
SERVICE PERSONNEL. THIS EQUIPMENT MUST BE EARTHED.
IT SHOULD NOT BE NECESSARY TO REMOVE ANY PROTECTIVE EARTH OR SIGNAL CABLE SHIELD
CONNECTIONS TO PREVENT GROUND LOOPS. ANY SUCH DISCONNECTIONS ARE OUTSIDE THE
RECOMMENDED PRACTISE OF BSS AUDIO AND WILL RENDER ANY EMC OR SAFETY CERTIFICATION
VOID.
For continued compliance with international EMC legislation ensure that all input and output cables are wired
with the cable screen connected to Pin 1 of the XLR connectors. The input XLR Pin 1 is connected to the
chassis via a low value capacitor, providing high immunity from ground loops whilst ensuring good EMC
performance.
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Quick Start - Reference 5
FDS-355 Omnidrive 5
1.0 Introduction 8
1.1 OMNIDRIVETM Compact
Loudspeaker Management System 8
1.2 Other features 8
1.3 Voltage setting 9
1.4 AC Power fusing 9
2.0 Unpacking 9
3.0 Mechanical Installation 10
4.0 Mains Power Connection 11
4.1 Mains power 11
5.0 Controls 12
5.1 Input section 12
5.2 Output section 14
5.3 Rear panel 15
Screen Layout 16
6.0 Default Screen 20
7.0 Utilities Menu 21
8.0 Inputs Menu 25
9.0 Outputs Menu 26
10.0 EQ Screens 30
11.0 Store and Recall 32
11.1 Storing 32
11.2 Recalling 33
12.0 System Headroom Management 34
Contents
Contents
4
Contents
13.0 Phase Compensation 34
14.0 Typical Applications 35
14.1 Stereo 2-Way with a mono sub-bass 35
14.2 Dual Bi-amp (Stage monitors) 35
14.3 5-Way zoning distribution 35
14.4 Mono 5-way 36
15.0 Quick Reference - How to ... 37
15.1 Use delays to Time align(R) drivers 37
15.2 Keep relative delays while delaying a
group 37
15.3 Name a band 37
15.4 Make a band full range 37
15.5 Add EQ for Constant Directivity horns 38
15.6 Loading custom logos 38
16.0 PC Card 39
16.1 Card types 39
16.2 PC Card format 39
17.0 System Security 40
17.1 Program lock 40
17.2 Lock mode 40
17.3 OWNER lock 40
17.4 OEM lock 41
17.5 Safe 42
18.0 Troubleshooting 43
19.0 Warranty Information 44
20.0 Specifications 45
Index
User Notes
Spare Parts Information
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Quick Reference
Quick Start - Reference
AC Power connection
The FDS-355 has a universal voltage AC Power input. Connect the FDS-355 to
AC Power with the lead supplied. The unit will switch on automatically (there
is no separate on/off switch). The display will show the default screen, with
the current program (if selected), and overall system response curves.
Audio connections
Connect the inputs and outputs as desired. All inputs and outputs are
electronically balanced, with Pin 2 hot signal (+ve). Do not put any audio
through the unit at this time.
Program settings
If your FDS-355 has been already configured with a program, you only need to
use the RECALL mode to set the parameters to that program.
Press RECALL. Turn the parameter wheel to select the designated program
(which has a number and name) and press RECALL again. Programs marked
with diamonds are OEM programs and have been designed to match specific
sound systems.
Some units will be locked (refer to section 17.0; System Security) to a
specific program. In this case most controls will be disabled and the unit will
be ready for use.
Recalling a program from a PC Card
To load a file from a PC card, push the card into the slot on the front panel of
the FDS-355. Press RECALL. Push the DOWN key to highlight 'Int', and turn
the encoder to select CPrg (or CAll for a full PC Card recall). Push the UP key
to return to file selection, and turn the parameter wheel to select the file. Push
RECALL again to recall the file.
Setting up a system
To configure your FDS-355, the mode of the unit should be decided upon
before setting up.
Once the Config is set (In the Utilities menu), the crossover points, individual
band delays, any EQ, and limiter thresholds can be set up.
To enter the Utilities menu, press the UP key from the default screen.
Configuring the FDS-355
The FDS-355 has 2 modes from which the unit can be configured: Stereo 2-
Way with sub (Stereo), or Mono 5-way (MONO). To select the mode you wish
to use, enter the Utilities menu, and press the UP key until you reach the
Config screen. Turn the parameter wheel to select the option you wish to use.
NOTE: When the configuration is changed, the unit will prompt for
confirmation of the action. If the STORE key is pressed, then the mode will
change, and DEFAULT VALUES WILL BE RESTORED. It is advisable to do a
'Store' before changing modes if you have set up a program.
FDS-355
Omnidrive
6
Setting the crossover points
Select the band to be edited by pushing the parameter wheel to cycle through
inputs and outputs. Note the LEDs above each channel change as the screen
changes.
Once the band has been selected, press the UP/DOWN keys until the first
crossover (Filter shape - Low slope) screen appears. Select the type of filter
shape by using the parameter wheel to cycle through the selection. Refer to
section 9.0; Outputs Menu for more info on crossover filter shapes. Pushing the
UP key from here will move to the Filter Frequency (Low slope) screen. Use
the parameter wheel to select the frequency. The high slope screen are then
access after this screen by pushing the UP key (once or twice).
Band delays
Use the UP/DOWN keys until the delay screen appears. The delay is adjusted
using the parameter wheel. Default settings for display and adjustment of
delay is in meters (m), but can be changed to milliseconds (ms), or feet/inches
(ft).
Bands can also be linked so multiple outputs can be delayed as one using the
delay link facility.
Adding EQ
Use the UP/DOWN keys to move to the EQ screen. The EQ shape can be
edited first. The shape of the EQ can be selected from one of the following by
turning the parameter wheel:
Hi-Shelf with 12dB slope (Hi12)
Hi-Shelf with 6dB slope (Hi6)
BELL
Low-Shelf with 6dB slope (Lo6)
Low-Shelf with 12dB slope (Lo12).
Pushing the UP key from the EQ shape screen will access the following
screens, in this order:
Filter Frequency screen
Cut/Boost screen
Filter Bandwidth screen
Setting the limiters
There are two screens associated with the limiters of the FDS-355, which
allow you to:
Turn the limiters on/off
Adjust the limiter threshold..
In the limiter on/off screen, turning the parameter wheel will select whether
the limiters are on or not. Pushing the UP key from this screen will access the
limiter threshold screen, and turning the parameter wheel will change the
threshold. The output meters are calibrated to this threshold, so the threshold
will show as '0' on the meter at all times, even if the limiters are off. The
thresholds are indicated in dBu, but can be changed to mV via the Limiter
Units screen in the utilities menu.
Quick Reference
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Automatic Phase Compensation
Automatic phase compensation is employed in the FDS-355 to maintain zero
phase difference between adjacent bands, even in 4 and 5-Way systems,
where the phase errors due to the effects of closely spaced crossover filters
can be significant. Phase compensation helps you to keep the response of the
system with the minimum of 'fiddle factor' adjustments.
Headroom Management System (H.M.S)
Headroom Management System manipulates the gain structure to make
maximum use of the dynamic range of critical components, resulting in lower
noise levels with sensitive amplifiers, where limiter thresholds are low.
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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
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The FDS-355 uses a switched-mode power supply which offers high efficiency
and low heat generation. This power supply accepts universal AC Power input
voltages in the range 100V AC to 240V AC (nominal), and requires no setting
adjustment for AC power voltages in this range. Minimum AC input voltage is
90 Volts, and the maximum is 264 volts.
Outside these ranges the unit will not work satisfactorily, if at all. Voltages in
excess of the maximum will probably cause damage. Voltages below the
minimum will cause complete system shutdown. The flash memory in the unit
will preserve all data in the event of a power failure.
1.3 Voltage setting
The Green-and-Yellow wire of the mains cord must always be connected to an
installation Safety Earth or Ground. The Earth is essential for personal safety as
well as the correct operation of the system, and is internally connected to all
exposed metal surfaces. Any rack framework into which this unit may be
mounted is assumed to be connected to the same grounding circuit.
The incoming mains power is fused within the FDS-355 by the fuse holder
mounted on the rear panel. Always replace with an identical 20mm x 5mm
'T' fuse, rated at 1A for continued protection from equipment damage and fire.
Spare fuses of the correct rating are supplied with the unit.
It is most important for continued safety that this specification is strictly
adhered to.
1.4 AC Power
fusing
Voltage/Fusing
Unpacking
As part of BSS' system of quality control, this product is carefully inspected
before packing to ensure flawless appearance.
After unpacking the unit, please inspect for any physical damage and retain
the shipping carton and ALL relevant packing materials for use should the unit
need returning.
In the event that damage has occurred, please notify your dealer
immediately, so that a written claim to cover the damages can be initiated.
See Section 19.0.
2.0 Unpacking
Fig 1.1 Mains fuse on
rear panel.
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Mechanical Installation
3.0 Mechanical Installation
A vertical rack space of 1U (1¾" / 44.5 mm high) is required. Ventilation gaps
are unnecessary (See Figure 3.1).
If the FDS-355 is likely to undergo extreme vibration through extensive road
trucking and touring, it is advisable to support the unit at the rear and/or sides
to lessen the stress on the front mounting flange. The necessary support can
generally be bought ready-built as a rack tray. As with any low-level signal
processing electronics, it is best to avoid mounting the unit next to a strong
source of magnetic radiation, for example, a high power amplifier, to help
keep residual noise levels in the system to a minimum.
Fig 3.1 Unit
dimensions.
Fig 3.2 Rack
dimensions.
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