I’m not the best person to address the question of vibrato, Joanna. This Mario Duenas recording of My Funny Valentine is a favorite here. I don’t have a clear understanding of what vibrato is. If the question is whether I practice trying to get the kind of effect Mario produces in this recording, the answer is Yes, and I am somewhat successful. I find that I’m best able to work on technique by copying what I hear rather than by trying to follow instructions. I’m quite sure that creating vibrato (a vibration) is not a matter of making repeated muscle movements, as nobody has that kind of muscle control.
The most meaningful explanations for melodica players are likely to come from professional woodwind players, I think. As for imitation, I have spent a lot of time trying to produce effects that I hear in the playing of some of our members, for example Lowboy Bootay, Quetscher, and Bruno. But others as well. I’m doing this by ear. I love this video, by the way, but the vibrato is just a bit too pronounced for my taste.