EigenD and Multiple Output Channels

Most, or at least many, audio IO devices for computers support ADAT optical IO although these ports are often configured as S/PDIF by default. The difference is that ADAT supports 8 channels while S/PDIF is stereo or Dolby. I'm not aware of any real-time dolby encoders so using S/PDIF is limited to 2 channels.

Also, although Mac headphone jacks also support digital optical, I'm not aware of any ADAT drivers for the Mac

In the audio window in EigenD, you can pick an output to use. The internal channel mixer mixes to stereo and is connected to an audio agent which, in the factory setups, has two audio channels numbered 1 and 2.

For use as a performance instrument you simply select an output device to which you have an audio system connected. To record, you need some way of routing the audio into your DAW such as Jack or Soundflower, an external mixer with virtual channels, or an IO device using loopback (or a return bus if it has one)

Typically, one might put an optical cable between the S/PDIF out and in which will then present the stereo audio to the DAW.

The problem is that the signal is pre-mixed in EigenD which is perfect for (stereo) performance but problematic if you want to do post on a DAW.

Here is the solution.

1. Set the optical IO on your interface to ADAT
2. Put an optical cable from the ADAT out to the ADAT in
3. Determine the channel numbers associated with ADAT (You can see this in AUDIO/MIDI setup on a Mac)
4. Open your instrument setup in EigenD and in Workbench
5. Locate the audio agent (lower right corner)
6. Open the agent (click the disclosure triangle)
7. Locate the audio inputs (yes, the inputs to the agent are the outputs from EigenD)
8. Open the list of outputs
9. Note that there are two, one for left and right, that they are wired to the channel mixer, and are channel 1 and 2
10. Click the + bubble on the output parameter (not on the individual channel)
11. A popup will appear, enter the 1st channel number associated with the ADAT output of your interface)
12. Repeat adding channels for the rest of the ADAT channels
13. Delete the wires from the channel mixer to channel 1/2
14. Add wires from the channel mixer to ADAT 1/2
15. Delete wires from the audio rigs you wish to separate to the channel mixer
16. Add wires from the desired audio units to the remaining ADAT channels

The result looks like this (click to enlarge):

Now just select the interface in your daw and create tracks for each of the ADAT inputs (not outputs).

In addition to recording things separately for post this will let you do things like creating a surround mix, ducking channels (live or inpost) and so on.