You can just click the midi monitor in band in a box and set the filter to the channel you want to see on your harmonizer. On mine you basically get triads of notes as groups, or you can set the option for more complex output.

At least with the midi monitor you can confirm the fact that x and y were sent on the midi channel of your choice.

I usually use all RealTracks to test, and you then see the only midi as set gs or gm at the start type of thing.

Not complicated, but I must say you can uncomplicate the whole she bang by using an external midi module set on channel 1 and then use 5 for solo channel and the harmonizer. That way you can embed changes to your vocal parts in the solo channel.

John Conley
Musica est vita