网络音频延迟
用法
var ctx = require ( 'audio-context' )
var delay = require ( './index.js' )
var oscillator = ctx . createOscillator ( )
var processed = delay ( oscillator , { time : 5 / 8 , feedback : 0.7 } )
oscillator . start ( ctx . currentTime )
oscillator . stop ( ctx . currentTime + 0.5 )
processed . connect ( ctx . destination )
