It was not a chain. The original store was on Westport Road in Kansas City, MO., just east of State Line , across the street from what is now Rudys Mexican Restaurant. They carried the high end of the time; McIntosh, Tandberg, JBL, Yamaha, etc. Eventually they opened a second store at about 105th and Metcalf, an oval shaped building, and then closed the original location. They expanded into microcomputers in the early 80's after David Beatty himself had sold the store that carried his name. They prided themselves also on their service dept, headed by a technician whose name I believe was Ray Fairfield.
I spent a fair amount of time hanging around there drooling over things I couldn't afford
The business eventually failed after it had been sold, no doubt aided by the proliferation of chains and junk equipment. Sadly, David Beatty took his own life with a leap off of a bridge.
Some of the remaining staff from the store eventually opened another high end shop in Overland Park, KS., called "Audioport". For some time, they used the line "The guys from Beatty's" in their ads... [edit: That store is now closed as well]
**Edit: In the interest of completeness, I should also add that another KC store is owned by former Beatty guys: Soundfx is owned by Robert Bruce. They seem to be primarily a home theater shop, but are one of the very few independent stores left in the KC area.