Thought you guys might be interested. Blockhead is a weird sample based DAW that does things its own way. No MIDI, no external plugins. But it does have a flexible tempo system, a cool loopback/sampling input, and all effects are momentary. And, Linux support!
I have used it and can confirm it works on Pop!_OS (an Ubuntu derivative). So far I've had a lot of fun. Worth checking out the video from the creator:
https://www.youtube.com/watch?v=P5fWPBOdrY8