aftersound vs reverb

aftersound

noun
  • A sound that persists or remains audible after its source has ceased to produce it; the perception of such a sound. 

  • The second, slower phase of decay in the sound made by a piano string when it is struck. 

reverb

noun
  • An electronic effect which simulates echoes or reverberations in the sound signal being processed. 

verb
  • To apply a reverb (electronic echo effect) to. 

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