Simplify the following text for a Grade 8 native English-speaking person.
Original: He has also played a good deal of chamber music , often with the pianist Emanuel Ax , with whom he has a close friendship back from their days together at the Juilliard School of Music in New York .
Simplified: He has also played lots of chamber music , often with the pianist Emanuel Ax whom he had met at the Julliard School of Music .