Simplify the following text for a Grade 10 native English-speaking person.
Original: Rostal played a wide variety of music , but was a particular champion of contemporary works such as BÃ la BartÃ k 's Violin Concerto No. 2 .
Simplified: Rostal played a wide variety of music , including many newly composed works such as Violin Concerto no 2 by BÃ la BartÃ k.