boom box vs high fidelity

boom box

noun
  • A powerful portable audio system for listening collectively to recorded or broadcast sound. 

high fidelity

noun
  • A high-quality reproduction of sound. 

  • The electronic reproduction of a given sound or image with relatively high accuracy. 

adj
  • Characterized by minimal distortion. 

How often have the words boom box and high fidelity occurred in a corpus of books? (source: Google Ngram Viewer )