It is possible to operate Orpheus without a FireWire connection to a host computer. This is done by setting up the unit as required using the Orpheus Control Panel applet whilst it is connected to a host computer via its FireWire interface, then placing the unit in standby by pressing the standby button, before disconnecting the unit from the host and power source. When the unit is re-powered, and detects that no FireWire connection is active, it reloads the settings which were previously stored.
Since all of the outputs have optional mixers within the Orpheus hardware whose inputs include all of Orpheus' input connectors, it is possible, for example, to connect the digital input pair to one or more analogue output pairs, and to mix one or more analogue input pairs to the digital output pair. The synchronization source and sample rate can be set in the usual way. Thus stand-alone mode can be used to configure a stand-alone D/A converter and A/D converter, with static mixing if required.
ADAT Direct mode allows Orpheus to operate as an eight channel analogue-to-ADAT and ADAT-to-analogue converter. ADAT Direct mode is activated by setting the ADAT control in the Unit Settings panel to 'Direct'.
In ADAT Direct mode it is possible to control Orpheus using the Control Panel applet in the usual way while Orpheus is connected to a host computer via FireWire. If Orpheus is not connected to a host computer, ADAT Direct mode can still be used as a stand-alone mode, by saving pre-selected settings using the standby button as described above.
Signal routing in ADAT Direct mode
The eight ADAT output (send) channels are fed directly from the eight analogue input channels. Any signals sent from the host computer over FireWire (if connected) destined for the ADAT outputs are ignored by Orpheus.
The eight channels sent from the host computer over FireWire (if connected) destined for the Orpheus analogue outputs are ignored by Orpheus, and replaced by the eight ADAT input (return) channels. This means that the analogue output DAW/Mix switch can still be used: in the DAW position, the analogue outputs are fed directly from the ADAT inputs; in the Mix position, the analogue output mixer can be used to mix the ADAT inputs with any of the other Orpheus inputs.
The ADAT inputs and analogue inputs are available to the host computer (if connected) for recording or monitoring if required. The ADAT outputs and analogue outputs appear to be available to the host computer (if connected) but are ignored by Orpheus. Orpheus' S/PDIF inputs and outputs, and headphone outputs, remain available to a connected host computer.
In common with all ADAT modes, ADAT Direct mode can only operate with all eight channels if the sample rate is set to 44.1kHz or 48kHz. At sample rates of 88.2kHz or 96kHz, ADAT Direct mode operates in SMUX mode, supporting only the first four analogue input and output channels. ADAT Direct mode cannot be selected at sample rates of 176.4kHz or 192kHz.
NOTE: Since ADAT Direct mode modifies Orpheus' normal signal routing, it is very important to ensure that ADAT Direct mode is not selected accidentally.