Alexander Schneider (1908–93) was a violinist, conductor, and teacher who played with RK in a violin-harpsichord duo in the 1940s and early 1950s. They performed at the Library of Congress and elsewhere under the patronage of Elizabeth Sprague Coolidge and toured the country giving recitals. RK and Schneider also made several recordings of Mozart's sonatas for violin and harpsichord. Schneider was a member of the Budapest Quartet for many years, although he left the quartet in 1944 and rejoined it in 1955. He played in numerous other chamber groups, including the Albeneri Trio, the Schneider Quartet, and the New York Quartet. He formed a close relationship with Pablo Casals and Rudolf Serkin. Schneider played and conducted for many years at the Marlboro Music Festival and the Casals Festival in Prades and Puerto Rico. In 1969, Frank Salomon and Schneider formed the New York String Orchestra Seminar, which offered young musicians an opportunity to study and perform under Schneider's direction each December in New York. Despite some conflicts, as indicated in several of the letters, RK and Schneider remained friends throughout their lives.

[November 1943?]

My Dear Ralph—

I had my reasons for not writing you before and as you could imagine a very simple one. Just today I told them that I am leaving the quartet after this season and they, of course, agreed the best time would be March first. Nothing more was said—of course, I expect some more arrangements about when and what to say, etc. Of course, I told them if they have any difficulty after March first, I shall certainly continue playing a few concerts with them till they get settled. I feel terrible bad, having a cold with temperature since five days and have to play and move all the time which makes it worse. Hope to survive my cold and be in N.Y. Tuesday morning—expect to hear from you there. My telephone no. is Plaza 5-5242.