I know this is a necrobump, and the person who asked the question probably won't be coming back, but I have some thoughts on this that somebody else might find useful. A few years back, I bought a cheap no-name melodica on eBay. It does the trick, but some of the reeds are out of tune. Turns out that this is a universal problem.
The good thing is that reeds can be tuned.
Melodica is seen as a toy, so it's doubtful that you'll find one that you can call a "pro" instrument, even when looking at Hohner, Suzuki, Yamaha, and the like. Given that, I'd go for something cheap and lightweight were I you.
|