so I figured that using pipewire to co-ordinate this would be the easiest way forward, except it turns out that it’s a (GUI) user space process, which doesn’t make sense on a server with no GUI users.
I’m not entirely sure what you mean by “(GUI) user space process”, but if it’s that it’s a systemd user process (e.g. it shows up when you run $ systemctl --user status pipewire rather than $ systemctl status pipewire, which appears to be the case on my system, where there’s one instance running per user session), then you probably can run it as a systemwide process, where there’s just one always-running process for the whole system. IIRC, PulseAudio could run in both modes. I don’t know if you have concerns about security on access to your mic or something, but that could be something to look into.
searches
Sounds like it’s doable. Not endorsing this particular project, which I’ve never seen before, but it looks like it’s possible:
https://github.com/iddo/pipewire-system
PipeWire System-wide Daemon Package (Arch Linux)
This package configures PipeWire, WirePlumber, and PipeWire-Pulse to run as a single system-wide daemon as the root user. This setup is optimized for headless media servers, HTPCs, or multi-user audio environments.










I have a KitchenAid hand mixer that’s been fine. If you’re happy with your KitchenAid stand mixer, seems that it might be reasonable to get the hand mixer version. I mean, you’ve already got a picture of one posted.
Note that I’m assuming that “variable speed” here translates to “discrete number of speeds in a given set of increments”, and not some “continuous-variable speed where you can just move a slider” thing.