double bass vs rebec

double bass

noun
  • The largest stringed instrument of the violin family. 

  • The deepest of all male voices. 

rebec

noun
  • An early three-stringed instrument, somewhat like a simple violin only pear shaped, played with a bow and used in Medieval and the early Renaissance eras. 

How often have the words double bass and rebec occurred in a corpus of books? (source: Google Ngram Viewer )