SMK-25MINI MIDI controller with TE KO II EP-133 works well
The SMK-25MINI MIDI controller (by Lekato or M-Vave) is pretty neat. Has a built-in battery + Bluetooth (that works!), as well as TRS-A MIDI out, in addition to the standard USB-C output. And I like the controls for the pitchbend & mod wheel.
Thanks to @andyLeer on the Adafruit Discord for the tip on these controllers!
Lekato SMK-25MINI on Amazon: https://amzn.to/3RBmcBx (affiliate)
Tribit Stormbox Bluetooth speaker on Amazon: https://amzn.to/4adSM3B (affiliate)