Here ADAT OUT on the OctoPre is connected to OPTICAL IN on a Scarlett 18i20 audio interface with a single optical cable. Both units are running at 44.1 kHz sample rate. The OctoPre’s clock source is set to INTERNAL, and the 18i20 is synchronised to it because its clock source is set to ADAT (via Focusrite Control).
This setup would, for example, enable up to 16 mic or line sources to be recorded in a DAW simultaneously, and would thus be ideal for recording a live band. Eight of the sources (those connected to the OctoPre) could benefit from the internal dynamics if necessary and have compression applied to control the dynamic range of the signals.
The setup would also be appropriate for any other audio interface which has an ADAT input.
Here ADAT OUT on the OctoPre is connected to OPTICAL IN on a Scarlett 18i20 audio interface with a single optical cable. Both units are running at 44.1kHz sample rate. The OctoPre’s WORD CLOCK IN input is connected to WORD CLOCK OUT on the Scarlett 18i20 with a BNC cable and the OctoPre’s clock source is set to W/CLOCK. The 18i20’s clock source is set to INTERNAL (via Focusrite Control), thus making it the sync leader.
The setup would also be appropriate for any other audio interface which has an ADAT input and a word clock output.
This example shows how to connect a greater number of DAW tracks to an analogue mixing desk for mixdown. The 10 analogue outputs of a Scarlett 18i20 interface are connected to desk Channels 1 to 10. Its OPTICAL OUT port is connected to an ADAT IN port of a OctoPre with ADAT > LINE mode selected. The OctoPre’s LINE OUTPUTS are then connected to Channels 11 to 18 of the desk.
The Scarlett 18i20 would normally be the sync leader in this situation, so its clock source is set to INTERNAL (via Focusrite Control). The clock source on the OctoPre is set to ADAT, so it is synchronised to the 18i20 via the ADAT optical connection.
The above channel counts are applicable at 44.1/48 kHz sample rate; four channels of audio could be transferred from the 18i20 to the OctoPre at 88.2/96 kHz.
This example shows a similar setup to Example 2, but using a Focusrite Clarett 8PreX allows operation at a sample rate of 96kHz (“SMUX-II” mode). Both units must be set to 96kHz; two optical cables are used, carrying four channels of audio each. The Clarett 8PreX is the sync leader.
This setup is also applicable with 192kHz sample rate (“SMUX-IV” mode); each optical cable will then carry two channels of audio.
This setup uses the OctoPre’s mic pre-amplifiers and compressors to provide a high quality “front end” for an analogue mixing desk. Use a pre-made loom to connect the OctoPre’s LINE OUTPUTS socket to eight line inputs on the mixing desk; this will need eight ¼” TRS jacks on one end and eight connectors appropriate to the desk’s line inputs on the other. If the desk’s line inputs are unbalanced, a loom with TS jacks at the OctoPre end will be suitable.
This setup would also be appropriate to use the OctoPre as an input stage with any type of eight-channel analogue device.
This example shows how the setup in Example 5 can be extended to add simultaneous digital recording, with or without secondary backup.
Because the OctoPre’s ADAT OUT ports are always active, you can record the performance on a DAW (or other recording device) with an ADAT interface. The example shows two Scarlett 18i20s: the ADAT IN port of each would be connected to the two ADAT OUT ports of the OctoPre, to provide eight-track recording (on the first) and a simultaneous eight-track backup on the second, at sample rates of 44.1 or 48 kHz.
Eight-track recording could still be achieved at 88.2 or 96 kHz, although each Scarlett 18i20 would provide 4 channels to the DAW; backup would not be possible.