Digital
Option
OctoPre Digital Option Operation Guide
Overview
The OctoPre digital interface card contains 8 separate
analogue to digital converters allowing all 8 OctoPre
channels to be accessed simultaneously on the rear panel
as either analogue or digital signals. The interface card is
available in two feature options: -
1.
AES/SPDIF/ADAT™
The 8 channels of the OctoPre are converted
simultaneously to either AES or SPDIF standard and to
ADAT™ standard.
2.
ADAT™
The 8 channels of the OctoPre are converted only to
ADAT™ standard.
These instructions refer to both feature options. Note:
Where the instructions refer to features that are only
available on the “AES/SPDIF/ADAT™” version these will
be marked with an “*”.
Digital Outputs
*AES
The 8 channels of OctoPre audio in AES digital format are
made accessible by connecting the AES cable to the 9 pin
D-type connector and switching “out” the AES/SPDIF
switch on the rear panel. The AES cable has four colour
coded XLR type connectors, each carries a pair of digital
audio channels as follows: -
OctoPre Channel
Number (Analogue
Output)
AES/SPDIF Connector Ring
Colour
Channel label in
digital stream.
1
2
BLACK
3
4
RED
5
6
YELLOW
7
8
BLUE
A
B
A
B
A
B
A
B
*SPDIF
The 8 channels of OctoPre audio in SPDIF digital format
are made accessible by connecting the SPDIF cable to the 9
pin D-type connector and switching “In” the AES/SPDIF
switch on the rear panel. The SPDIF cable has four colour
coded Phono/RCA type connectors and pairs of digital
audio are sent down each cable, see above for colour to
channel identification.
ADAT™
The 8 channels of OctoPre audio in ADAT™ format are
made accessible via two light pipe sockets. The function of
these connectors is dependent upon the sample rate set
for digital conversion on the front panel. At either
44.1KHz or 48KHz sample rates both sockets transmit all
8 channels of digital audio simultaneously giving two
identical parallel outputs of all 8 channels. At either
88.2KHz or 96KHz sample rates the digital outputs are
spread across the two connectors as follows: -
Audio transmitted in digital stream
OctoPre Channel
Number (Analogue
Output)
Sample Frequency
44.1KHz or 48KHz
Sample Frequency
88.2KHz or 96KHz
1
1
1 (1-4 connector)
2
2
2 (1-4 connector)
3
3
3 (1-4 connector)
4
4
4 (1-4 connector)
5
5
1 (5-8 connector)
6
6
2 (5-8 connector)
7
7
3 (5-8 connector)
8
8
4 (5-8 connector)
Note: The operation of splitting the 8 channels of
88.2/96KHz digital audio across two light pipe sockets
conforms to the S/MUX
2
standard. This standard is
required for the ADAT™ connectors to transmit at
88.2/96KHz because of a limitation in the transmission
speed of the original ADAT™ standard. The S/MUX
2
standard of operation can only be used when connecting
to equipment capable of receiving audio data conforming
to this standard, check your equipment operating
instructions for compatibility.
S/MUX
2
is the copyright of Sonorus Inc, Newburgh, NY, USA
ADAT™ is the trademark of Alesis Corp
