am·pli·fy

ˈampləˌfī/

verb

verb: amplify; 3rd person present: amplifies; past tense: amplified; past participle: amplified; gerund or present participle: amplifying

          to increase the volume of (sound), especially using an amplifier."the accompanying chords have          been amplified in our arrangement"

make louder, louden, turn up, magnify, intensify, increase, boost, step up, raise  "the sound from an electric guitar was meant to be amplified" increase the amplitude of (an electrical signal or other oscillation). cause to become more marked or intense.  "urban policy initiatives amplified social polarization"