Assertion: choir's music | /r/HasProperty | unaccompanied
Facets:
Source sentences:
text: Accompanying instruments vary widely, from only one instrument (a piano or pipe organ) to a full orchestra of 70 to 100 musicians; for rehearsals a piano or organ accompaniment is often used, even if a different instrumentation is planned for performance, or if the choir is rehearsing unaccompanied music.