Here’s a concert I wish I could have attended. A young Glenn Gould (greatest Bach interpreter since Bach although I heard Felix Mendelssohn was pretty good too) with Leonard Bernstein in his prime conducting the New York Philharmonic (I think) playing the first movement of JS Bach’s Keyboard Concerto in D minor, BWV 1052.
There is a famous incident of a Gould performance of the Brahms Piano Concerto 1 when he and Bernstein had such a disagreement on the tempo (Gould wanted to play it really slow) that Bernstein got up on stage beforehand to make a disclaimer. That performance with speech is recorded and someone has uploaded it to YouTube.
Gould gave up performing in 1964 at age 31. Notice how low he likes to sit at the piano. He used to bring his chair with him when he toured. One of my favourite films is “Thirty two short films about Glenn Gould,” which I definitely recommend seeing.