I don’t see why it should be any different – any tuning differences would be due to air pressure which is pretty variable in both cases! I can test it though, I was was going to do a “tuning inventory” on it anyway just to see what shape it’s in.
I write music software (that people don’t buy a whole lot of), and I might be able to throw together an online tuning web app that can:
– record an analyze a series of sounds (you shouldn’t have to break them up, just make sure they are monophonic and clear)
– check the frequencies for each “note”. They change over time, so you’ll get to pick which ones you want to pretend are the actual tuning.
– compare it with the idealized version of that note for the tuning system you want (it might be 1/4 comma mean tone based on 442 Hz or something like that)
– show which reeds need the most attention.
– lets you save it for comparison later
– optionally output a tuning file so if you like your out-of-tune melodica, you can convince a synthesizer to match its pitches. This would be using MIDI 2.0 or similar tricks.