MIDI Monitor is a utility for Mac OS X which displays MIDI signals in a variety of formats. It can watch both incoming and outgoing MIDI streams, and can filter them by message type and channel.
What’s new in version 1.5.4
Updated on Jul 21 2023
Fixed a crash when receiving large amounts of MIDI data by "spying" on the output of another app.
On El Capitan (10.11.6) I get a "could not make a connection" driver warning on every launch, but it only affects the ability to "spy" on other MIDI apps, not the ability to monitor MIDI messages on input and output ports. Other than that, it's worked fine for me; can't complain for the price!
another great one !!!!
thanxx Kurt for this great little tool !!!
with SysEx Librarian together ....what do you need more to handle your MIDI stuff .....