I just played the melodica 37 key instrument, and it sounds wonderful! It doesn't take much air, to get sound, and it can be a little loud, but you just blow softer to lower the volume. At first, I thought I was missing the mouthpieces and flex tubes. But they were in a compartment within the bag. Just be sure you look at the entire contents of whichever model you get, to make sure you got everything. I look forward to learning more about playing this instrument.