I’m looking for a good small/compact midi keyboard (1 or 2 octave is enough), preferrably with midi out TRS (or MIDI DIN), and battery powered. something of a mod wheel (or strip) would be nice too.
I’m afraid this doesn’t exist?
I have an arturia keystep 37 already, but its usb powered, and quite large.
Anything that takes USB power can be powered by a battery pack. 5v is 5v, the device has no way of knowing whether it is being powered by a battery or a power adapter. Anything that takes barrel power can almost certainly be powered by a battery pack, but it may take a little more effort to find a suitable cable.
Keyboards like the Samson Graphite M25 or an Akai LPK25 are probably closest to what you want, but you will need something else to host and power them. RK006 should do the job.