alto vs double bass

alto

noun
  • A person or musical instrument that performs the alto part. 

  • A musical part or section higher than tenor and lower than soprano, formerly the part that performed a countermelody above the tenor or main melody. 

  • An alto saxophone 

double bass

noun
  • The largest stringed instrument of the violin family. 

  • The deepest of all male voices. 

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