Just to add to the story which is no doubt but hopefully accurate, Pat Marrazza did indeed have an accordion school and sales store in Montreal, and that was in the 40's or earlier. How do I know this? In mid- 1940's my teacher in Hamilton Ontario owned a Marrazza model, sold it and purchased one of the new Excelsior Symphony Grands from Pat as I remember him telling me. And Hamilton professional accordionist Jack Slater also owned a hi-end Marrazza. I believe Pat may also have visited Hamilton to discuss sales for the Viola's growing accordion school and business - which incidentally grew to over 325 students! That was in the late 40's- early 50's...
My 1949/50 Symphony Grand was made in New York - not Italy -- - serial # on the back of the keyboard # 9999! Sold it to a friend (Ettore L) who taught in Chatham Ontario, then I purchased an updated model with mute and mikes in '54 which I still have. and I learned years later the first one (9999) ended up in Montreal -- perhaps tragically lost in a fire as reported to me, but one never knows... if it's still here. I'd like to know..
Yes, Pat, as he was known then, purchased from several accordion factories in Italy and placed his name on them. Cannot offer any comment regarding their quality. Likely varied according to quality of parts and their availability. Have a mid-size 2/4 in my collection.
I've already given more details re his son-in-law Jack Wright who took over the Excelsior/Excelsiola/Accordiana line when Pat retired sometime in late 40's or early 50's and opened Excelsior Supply Co. on Albert Street near the old Forum along with Minnie Ceretti as secretary and office manager..
When operating a service centre years later, I had occasion to service some Marrazza accordions and found them of good quality -- provided they were well taken care of... and that's the key to quality of used accordions. E.g., I own a 1934 Excelsior Pietro Deiro model in mint condition along with the original case!! No, I was not there when built in case you wondered, far away distance- but not time-wise!!
Hope this adds a bit more to your inquiry re Marrazza accordions.