TromboneChat

I’m interested to know about the timeline of Conn’s counterweight design.

I’m wondering approximately what year the factory went to the modern design that reads simply “CONN”

I’m guesstimating it was around ‘53 or ‘54.

It's described as new in the 1955 catalog, but the catalogs weren't updated annually, so your guess is probably correct.

Here is a wealth of information:https://www.saxophone.org/museum/publications
As per your inquiry, I copied the following: