On my final evening in Los Angeles, I attended an exquisitely executed performance of Schubert’s sublime string quartet No. 13 in A minor and string quintet in C major in the Frank Gehry-designed Disney Concert Hall. I couldn’t help wondering what Franz Schubert would have thought of the marvelous acoustics and the performance of his music in this postmodern fantasy of a building with its abstract, soaring curves and its sharp points and edges, with rhythms flying free of gravity.