AudioBox AB64 Board Installation
updated 8 September 2005
The audio channel capabilities of the AB64 are field upgradable to
a maximum of 64 channels by adding plug-in DSP and Analog circuit
boards. The step-by-step instructions for adding in DSP and Analog
boards are provided on this page. Adding a DSP board adds 16 input
and 16 output channels to the mixing matrix. Adding an Analog board
adds16 channels of analog input and output to the matrix. It is not
necessary to have analog channels attached to all channels of the
matrix. For example, one may wish to use CobraNet to feed signals
into and out of some of the matrix channels. Contact
Richmond Sound
Design with any questions regarding AB64 configuration.
The AB64 Chassis
The AB64 chassis is illustrated in the drawings below. There is
always exactly one CPU board in the unit. There can be zero up to
four DSP boards installed at the location designated "DSP Board
Stack". Similarly there can be zero up to four Analog boards
installed at the location designated "DSP Board Stack".


General Instructions
THE FOLLOWING PRECAUTIONS MUST BE
TAKEN TO ENSURE THAT STATIC DISCHARGES DO NOT OCCUR WHEN HANDLING
CIRCUIT BOARDS. FAILURE TO FOLLOW THESE STATIC DISCHARGE PRECAUTIONS
MAY CAUSE DAMAGE WHICH IS NOT COVERED UNDER WARRANTY.
1. WORK SHALL BE PERFORMED AT A STATIC-FREE
WORKSTATION.
2. THE AB64 CHASSIS MUST BE CONNECTED DIRECTLY
TO GROUND WHEN INSTALLING OR REMOVING CIRCUIT BOARDS. THE POWER
SUPPLY CABLE DOES NOT GROUND THE AB64 CHASSIS; A WIRE MUST BE
CONNECTED DIRECTLY FROM THE CHASSIS TO A GROUNDED POINT.
3. PERSONS HANDLING CIRCUIT BOARDS MUST
DISCHARGE STATIC BY TOUCHING A GROUNDED SURFACE (SUCH AS THE GROUNDED
AB64 CHASSIS) BEFORE OPENING PACKAGES CONTAINING CIRCUIT BOARDS AND
BEFORE REMOVING BOARDS FROM THE UNIT. PERSONS MUST EITHER WEAR A
GROUNDED WRIST STRAP OR MAINTAIN CONTACT WITH THE GROUNDED AB64
CHASSIS DURING THE HANDLING OF CIRCUIT BOARDS.
4. STACKING CONNECTORS MUST BE GROUNDED TO
DISCHARGE STATIC BEFORE THEY ARE INSERTED INTO CIRCUIT BOARD
SOCKETS.
IN ADDITION, CARE MUST BE TAKEN TO ENSURE ALL
CIRCUIT BOARD CONNECTOR PINS ARE LINED UP AND CONNECTED PROPERLY TO
THE CORRESPONDING SOCKET BEFORE POWER IS APPLIED. FAILURE TO DO SO
MAY CAUSE DAMAGE WHICH IS NOT COVERED UNDER WARRANTY.
- There are four levels at which Analog and DSP boards can be
located, numbered 1 through 4.
- The DSP board at level 1 plugs into the CPU board. Boards at
levels 2 through 4 plug into the DSP boards one level down.
- If there is an Analog board at level 1, it must be installed
before the DSP board at level 1. In this case, the DSP board at
level 1 will plug into the Analog board at level 1. The same
applies when there are Analog and DSP boards at levels 2 through
4.
- A DSP board must be installed at level 1 before an Analog
board can be installed at level 2. The same applies at higher
levels.
- Nylon hex spacers are used between boards to provide
mechanical support. The threads of the nylon spacers can be
damaged by overtightening. When installing, turn the spacers no
more than 1/4 turn after the mating surfaces make contact.
- The highest board in the stack is secured using 6-32 x 1/4"
machine screws and lockwashers. When installing, turn the screws
no more than 1/4 turn after the mating surfaces make contact.
- (4) stacking connectors are used to make the electrical
connections between DSP boards.
Installing Analog Boards
- Ground the AB64 chassis.
- Unplug the power cable from the unit and remove the top cover.
- Remove the plate coving the openings in the chassis where the
analog signal connectors will go.
- Remove the (8) jack screws from the four analog signal
connectors along the bottom edge of the board.
- Remove the (3) machine screws securing the Analog board
currently at the top of the Analog Board Stack (if any).
- If installing at levels 2, 3 or 4, install 3 nylon hex spacers
where the machine screws were removed in the previous step.
Tighten at most 1/4 turn after mating surfaces make contact.
- Place Analog board into position.
- Install (8) jack screws from the outside of the chassis into
the analog signal connectors.
- If this Analog Board is now at the top of the Analog Board
Stack, use (3) 6-32 x 1/4" machine screws with lockwashers to
secure the board. Tighten at most 1/4 turn after mating surfaces
make contact.

Stacking Connector
Installing DSP Boards
DUE TO THE SENSITIVITY OF
HIGH-DENSITY PROCESSOR CHIPS TO STATIC DISCHARGE, THE AB64 DSP CARDS
ARE EASILY DAMAGED BY STATIC DISCHARGE. READ THE GENERAL PRECAUTIONS
ABOVE. FOLLOW THE FOLLOWING DIRECTIONS EXACTLY.
- Ground the AB64 chassis.
- Unplug the power cable from the unit and remove the top cover.
- Remove the (4) machine screws securing the DSP board currently
at the top of the DSP Board Stack (if any).
- If installing at levels 2, 3 or 4, install 4 nylon hex spacers
where the machine screws were removed in the previous step.
Tighten at most 1/4 turn after mating surfaces make contact.
- Discharge static from a stacking connector by touching all of
the pins simultaneously to the grounded AB64 chassis. Plug the
stacking connector into one of the socket connectors other than
J4B on the bottom of the DSP board. (The DSP chips, etc. are on
the top of the board.) Do not place a stacking connector into the
socket connector labeled J4B - this is where the Analog board (if
any) plugs in. Be sure the connector is fully seated and all
connector pins are lined up with the corresponding holes in the
socket connectors. It does not matter which end of the stacking
connector goes into the socket connector on the DSP board being
installed. Repeat until all four connectors except J4B have
stacking connectors plugged in.
- Carefully line up all the pins of all the stacking connectors
with the holes in the socket connectors at the level below,
including those on the Analog board (if any).
- Press firmly down on the DSP board until it fully seats.
Ensure connection to analog board is good by pressing DSP and
analog cards together at connector.
- If this DSP Board is now at the top of the DSP Board Stack,
use (4) 6-32 x 1/4" machine screws with lockwashers to secure the
board. Tighten at most 1/4 turn after mating surfaces make
contact.
- NOTE: DSP board at level 4: If the header labelled JTAP
has vertical pins, a plastic collar must be installed over the
header when a DSP board is installed at level 4 to prevent the
chassis cover from making contact with the header pins. Current
revisions of the DSP board use horizontal pins for the JTAP header
and do not require this collar. Contact
Richmond Sound
Design if the collar is required and was not supplied.
- Power unit on. If the installation was successful, the LCD
display on the front panel will indicate the new matrix size.
Special Case: No Analog Boards Installed
If there is one or more DSP boards installed and no Analog boards
are installed, a jumper is required on the bottom of the DSP board at
level 1 for the AB64 to function (DSP boards at levels 2 and above do
not require this jumper.). Contact
Richmond Sound Design
if the jumper is required and was not supplied. This jumper goes
between pins J4B-A1 and J4B-B1. See drawing below.
