I've tried every major DAW and none of them seem to have really thought through hardware synth workflow - it's always takes some tedious trial and error to get everything set up right. However, I've figured out a setup in Bitwig that I'm really happy with so I'd like to share some tips to help others.
First, the Basics:
- Under Settings -> Audio, you'll need to set up the inputs for each synth on your audio interface. I find it helpful to name each input for what synth is plugged into it, even if I have to change that periodically.
- Under Settings -> Controllers, any synth you want to record MIDI from should be added as a controller. I usually add them as "Generic" "MIDI Keyboard".
Tracks and Devices:
- I recommend creating a group track for each synth, so both the return audio from the synth and any recorded audio tracks can be routed through the same effects chain.
- Within each group, add an instrument track with an "HW Instrument" device. Set the MIDI output and audio return here. In the bottom left of the "return" section is a button to automatically detect latency by sending a short note to the synth and measuring the time before audio comes back.
- The leftmost pane in Bitwig's UI allows you to change which MIDI controllers control the track (defaults to "All Ins", near the bottom). For keyboard synths, I usually set them to be controlled only by that synth's MIDI input. That way I can arm multiple synths for recording at once and play them independently.
- To avoid doubled notes without using "local off" on your synth, you can disable monitoring with the little speaker icon button to the left of the input selection in the previous step.
- If you'd like to automate loading a patch, click "Note FX" on the HW Instrument to expand that section and add a "MIDI Program Change" device. Importantly, DESELECT "Chain Only" or it won't work. Make sure it's in the blue Note FX section and not the gray FX section. The settings for bank changes often take some trial and error, as different synths represent their banks differently.
- If it's a multitimbral synth, duplicate this HW Instrument track for each timbre and change the MIDI channel setting accordingly.
- If you want an audio recording, just right click a MIDI clip in the HW Instrument track and select "Bounce". This should create a new audio track under the same group, thus routing it through the same effects. You may want to extend your MIDI clip a bit to catch any release or reverb tails.
Presets:
One of the nice things about Bitwig is you can save all the setup you've done on a HW Instrument device for quick recall, including the attached program change. That means you can save individual patches/presets on your synth as presets in Bitwig's browser.
And, of course, once you have everything set up the way you want, you can save the project as a template to get started quicker next time.
I hope all this is helpful to someone - let me know if you have any questions!
Edit: Added a couple more tips under Tracks and Devices that I forgot to mention.