Thank you! You’ve told me the main two things that I wanted to know (that build quality is similar, and that the range overlaps with the Soprano model, not the Alto). Really, what I wanted to know is if my “next” vintage button-style Hohner melodica purchase should be the Alto or Soprano, and you’ve answered that.
I really love this little guy. I have taken it apart (mainly to clean it), and although I only have one other Melodica to compare it to, I have extensive experience with Harmonicas (including reed work and other custom modification), and to my eye, the build quality of this Melodica is excellent. The gaps were all set very well, the sizing of the reed slots were very tight, and the instrument thus produces a really nice tight focused sound (contra to my modern “Student 32”, which I assume was made in China from the quality of the reeds and reedplates, and which consequently produces a very “airy” tone). The only negative I could find about this vintage Melodica was that the gasket was not really fully airtight anymore, and one of the screw holes for the back plate was stripped because it’s just a hole in the plastic body with a “wood” screw, not a machine screw into a properly tapped hole. I expected some of that, and I think I can fix it with a tiny dab of epoxy in the stripped screw hole to give the screw something to bite onto. Other than that, this is a very high quality instrument, and I really really really love it!