New owner, On Catalina - how can I get samples into this thing?

[PofM]

Convert WAV to SDS using whatever app you want, e.g. SoX or Audacity can do it

Then transfer the SDS file using something like Sysex Librarian.

Edit: this thread covers exactly your situation:

Transfer samples from/to MachineDrum

Helllo there! Question … I’ve dusted off the old MD UW+ again and wanted to upload some samples to it. C6 does not seem to work on 64 bit Catalina though. I read many articles on the issue but was not able to find any alternative. The main alternative mentioned is SysEx Librarian but as far as I know, this utility cannot be used to transfer wav samples to my little silver box. Does anybody know of any alternative to use for transferring samples to my MD? Thank you!