class act vs instrumentalist

class act

noun
  • Someone or something whose performance is excellent. 

  • An excellent performance. 

  • Someone or something who is generally well-mannered, conscientious, etc. 

instrumentalist

noun
  • One who plays a musical instrument, as distinguished from a vocalist. 

  • An adherent of instrumentalism. 

How often have the words class act and instrumentalist occurred in a corpus of books? (source: Google Ngram Viewer )