This records the pulse audio stereo output (all desktop output audio) and stereo mic input to a 4-channel audio file. The only thing new here over the above examples is -filter_complex amerge.
I’m still not sure how to specify which hardware channel gets mapped to which file channel, but it’s a start.
And I guess I could make that a little more legible:
-f pulse -i alsa_output.pci-0000_00_1b.0.analog-stereo.monitor \
-f pulse -i alsa_input.pci-0000_00_1b.0.analog-stereo \
-filter_complex amerge 4_chan_test.wav
I’ll give it a go tomorrow with my audio interface to see if I can record 8 audio channels without issues.
I don’t know what for (other than being really light weight), but I might like to have a straight up handy dandy pre-configured recorder or 3 available from the command line. I’m just imagining here typing rec -riff, rec -song, or rec -band, and everything is configured and rolling for those respective situations without any bs and distractions. And likely with video capture to boot. Of course, input levels would still need to be configured, and I think ffmpeg could output some numbers for checking levels. Btw, my run with a Zoom portable recorder didn’t last long. That thing really sucks to use. So much menu diving and and page changing to do very basic things, and it still can’t do some very basic things. A handheld 4-track it is not. I bet something like a Raspberry Pi could be though.
It seems like this could be useful for scripting drum samples too. It’s almost too bad that I got rid of my e-kit. But not really. Real drums rule. But I don’t get to play them much.
And of course, the nice thing here is that ffmpeg is going to already be installed for any linux desktop. So hopefully just some bash scripting can make it a pleasure to use.