hit.mp3
miss.mp3
from https://www.adobe.com/products/audition/offers/AdobeAuditionDLCSFX.html?cq_ck=1407955238126&wcmmode=disabled
player1_wins.mp3
player2_wins.mp3
from http://soundfxcenter.com/download-sound/mkd-chess-player-1-wins-sound-effect/
winner.mp3
from Apple Sound Effect - Background Music