This particular instrument is like a compact light weight 2/4-reed double chamber jazz version of the famous Scandalli Super VI, made for Aldo Mencaccini. Aldo is the founder of BELL accordions and a legendary accordion master-technician. He was on the original design team for the Super VI. (His American made Bell 4516 was used as a prototype for the early Scandalli Super VI models, often referred to as 2S and 4S models because of the grill ornaments at the time.) He was so impressed by the Scandalli factory and team the company put together for the development of the Super VI line that he had his Bell 25xx series accordions made by Scandalli. This particular accordion looks like a custom order not found in any of the 1950's Bell catalogs I have.
Here is a link to a shared Dropbox folder with sound samples. Please, listen with headphones to fully appreciate the tonal quality of the instrument:
acquired this accordion from Alex and Bell accordions when the NYC
store closed. I didn't know Scandalli ever made such a 2/4 reed
double chamber model and was eager to play the instrument. After
fresh wax and complete voicing and tuning it sings. The compression
is great. The reeds are very responsive and you can play the
instrument without effort. This is the lightest and most compact
double tone chamber accordion with full size keyboard that I have
played. The body is slimmer than the Sonola Ernie Felice model (the
jazz accordionist's standard in this class). The warm mellow tone
will remind you the 1950's Supper VI. Whether you want to extend you
professional playing career and save your back or you simply want to
enjoy the heart melting tone of this fine accordion without carrying
the weight of the larger Super VI model this instrument will be
perfect for you. It is in tune and ready for a recording session.