My first idea is that if it has 3 keyboards and 120 bass, it ain't a
concertina.
Peter
I don't know that this helps establish a value, but I have sheet music with
a picture of Pietro Frosini on the front, with his three-right-hand
keyboards. If yours is similar, it's a pretty interesting item (and a piano
accordion, most likely).
Regards,
Bryant Russell
Plymouth, MI
A kind member of this group emailed me the right answer:
"Frosini played a three-row chromatic, B system.
His buttons were actually key tips and the piano appearance was cosmetic to
fool the public into believing he was using a piano keyboard accordion.
So, in essence, the white key tips in three banks are like the three row
chromatic buttons.
The black keys are false notes.
To play the piano keyboard portion as such, is not possible."
I appreciate the correction, and share with the group (and thanks too!)