Simplify the following text for a Grade 8 native English-speaking person.
Original: There are composers however who , in writing a piece in D minor with B-flat clarinets , will have them change to clarinets in A if the music switches to D major .
Simplified: However , when some composers write a piece in D minor with B-flat clarinets , they change to clarinets in A if the music changes to D major .