Before going through the setup steps, be sure to confirm that you have the matching software and firmware installed. Both units need to be on the firmware from the same installer release for them to sync properly.
Connect both units to your Mac via USB (use a powered hub if your Mac has USB 3.0 ports), launch the Symphony I/O Firmware Updater from your Utilities folder and confirm that the firmware is up to date for each unit. Select 'Symphony I/O 1' in the drop-down menu of the firmware updater app to check the 1st unit's firmware versions. After confirming the firmware is up to date for the 1st unit, select 'Symphony I/O 2' from the drop-down menu and confirm the firmware is up to date for the 2nd unit as well. When you're finished, quit the firmware updater and follow the steps below. Click here for help with Symphony I/O Firmware Updater.
To connect 2 Symphony I/Os to a Symphony64 Thunderbridge or PCIe card, follow the steps below in the exact order:
- Connect the Main Port of Unit A to Port 1 (chs 1-32) of the Thunderbridge, using a PC-32 Symphony cable.
- Connect the Main Port of Unit B to Port 2 (chs 33-64) of the Thunderbridge, using a PC-32 Symphony cable.
- Use 2 BNC cables to connect the Loop Sync output of Unit A to the Loop Sync input of Unit B and the Loop Sync output of Unit B to the Loop Sync input of Unit A. Make sure you're using the LOOP SYNC jacks and not the Word Clock jacks.
- On Unit A, press in and hold on the front-panel right-side encoder knob until you come to the Audio Mode menu. Scroll until it says 'Symphony' and then push in on the encoder knob again to restart the unit in Symphony mode. Do this to Unit B as well.
- Launch Apogee Maestro2 from your Applications folder, go to the 'System Setup' tab and make sure the "USE LOOP SYNC" check-box is CHECKED. Quit Maestro.
- On your Mac, launch 'Audio MIDI Setup' (Applications Utilities 'Audio MIDI Setup'). Make sure 'Symphony64' is highlighted on the left-side device column. On the right-side, set the 'Source' to 'Ports 1-2: Chs 1-64'. Quit Audio MIDI Setup and restart the Mac.
- Once the Mac restarts, you need to wait until the units have finished configuring before launching Maestro or ANY other software. This can take a couple minutes. You'll hear relays clicking back and forth and you'll see the "!" icon on the front-panels appear and disappear. When this stops after a minute or so and both units are configured, Unit A should say 'INT' and Unit B should say 'LOOP'.
- As soon as both units appear to be configured and Unit A says 'INT' and Unit B says 'LOOP', launch Maestro and confirm that both units show up as expected.