M-Audio CO3 [7/8] Aes ebu input mode

S/PDIF streams for you.

Input Source Modes

Depending on the type of input selected, the CO3 functions will differ

according to what conversions can be done, and which cannot. The SCMS

mode settings behave the same way for both TOSlink (Optical S/PDIF) and

S/PDIF (Coaxial) source signals, and whichever is chosen as the source, that

signal is output to both the optical and coaxial S/PDIF output jacks. The

AES/EBU signals require special handling since they don’t carry SCMS

information – more specific information is available below.

Coaxial or TOSlink (optical) S/PDIF Input Modes

When the source is set to coaxial (RCA-type jack) or optical (TOSlink jack)

S/PDIF, "Pass-Thru" becomes the default SCMS mode. Since an S/PDIF

input signal carries SCMS information, all four SCMS modes are available.

When SCMS Pass-Thru mode is selected, the data bits coming into the CO3

S/PDIF inputs are directly copied to the S/PDIF RCA and TOSlink output

jacks unaltered, and the CO3 does a true conversion to the AES/EBU format

(minus the SCMS bits of course). This is the only setting in which true

S/PDIF to AES/EBU conversion takes place – Source set to either S/PDIF

input, and SCMS set to Pass-Thru.

When SCMS modes other than Pass-Thru are used, the associated SCMS

LED will blink. This indicates that the unit is in a SCMS stripping mode and

therefore the AES/EBU output is invalid; only the coaxial and optical

S/PDIF outputs are valid.

AES/EBU Input Mode

When the source is set to AES/EBU, "None" becomes the default SCMS

mode. Since an AES/EBU input signal carries no SCMS information, only

three of the four SCMS modes are available. SCMS Pass-Thru mode

becomes nonsensical because the AES/EBU source has no SCMS data to pass

through. Therefore, Pass-Thru mode is not available from the front panel

when AES/EBU is selected as the source.

In all three SCMS modes, the data bits coming into the CO3 AES/EBU input

are directly copied to the AES/EBU output jack unaltered, and the CO3 does

a true conversion to the two S/PDIF format output jacks. Because there is

no SCMS data in the incoming stream, the CO3 places SCMS data in the

S/PDIF output streams according to the SCMS setting on the front panel.