The missing step for me was finding the Focusrite icon in systray, right clicking, selecting “Expose / Hide Windows Channels” and ticking “S/PDIF L + R”. This channel was then available to Audacity.
I’ve taken a screenshot while recording Dorico into Audacity, but it works equally with capturing sound from my web browser, which I do when transcribing music and lyrics.
I had tried this route before but had ticked “Loopback L + R” as the Windows channel since it’s the Loopback function of Focusrite that send the incoming stream back to my computer. But that didn’t work and I just got a “flatline” when recording in Audacity using the default settings. Then I thought why not try another setting. Ah, joy!
What was particularly confusing was that in Focusrite I do have to send my mix to Loopback in order to send data to my computer at all, yet I don’t need to select the Windows channel saying Loopback. I can only guess that the Focusrite Loopback sends both analogue and digital data back to my computer, and that I needed to select “S/PDIF L + R” as the Windows channel in order to access the digital data, which is what Audacity requires. Another confusion was that I use an S/PDIF cable to connect the 8i6 to my speakers, but there is no S/PDIF cable connection to my computer (so I was able to discount that). Guessing again, perhaps Focusrite identifies the incoming digital data to Windows as “S/PDIF L + R”. S/PDIF is of course an audio connection standard for transmitting high-quality digital audio, not just a label for a particular cable.
If anyone can enlighten me on these two guesses I’d be grateful.
I’m sure there are other ways to do what I want to do, but Audacity is free, and I find it easy to work with on an occasional basis. Labels are particularly useful. I’m using the latest version of Audacity 3.1.2.