So believe it or not, I am finding that wearing an old pair of Bose noise cancelling headphones seems to work really well for personal monitoring. The headphones cut down on the stage volume. (I play my studio monitors really loud to imitate a stage environment.) They also provide a really clear, detailed reproduction of my processed piano harmonica signal. I play so much better when I can hear every nuance of my instrument. And I don’t have to carry an amp.
I take the spare line-out signal from my direct box and run it–using a microphone cable–to a broadcast-quality, battery-powered microphone preamp attached to my belt. Then I plug my headphones into the preamp, which also has a volume control. I have tried this in the past with Shure in-ear monitors, but the headphones did not work well. As crazy as it sounds, I like the Bose setup better.
The two issues are: First, I will have to perform on stage with headphones on. (I don’t care about this except I will not be able to wear my bluesman hat.) Second, my sound will be in the hands of the sound man (okay) or some band member’s friend–who does not know about music–saying the “melodica is too load” or “too soft” (not okay).
I will try this out at the next rehearsal to get real life experience with it.