I remember Charlie pounding out a Bach - Busoni edition of the Passacaglia in c minor on an upright piano at the Fisk house in North Cambridge. This was in the 1940's when I arrived to pick up Charlie's sister for a date.
I visited the Holtkamp shop in Cleveland on Charlie's first day of employment. I was visiting Fenner Douglass at Oberlin in 1949 just before Frank and I started Hubbard & Dowd. Charlie had just started work at Holtkamp and Walter offered me a job that day (I declined declaring my interest in harpsichords).