connect(unit) {
    var u = unit || p5.soundOut.input;
    this.output.connect(u.input ? u.input : u);
    if (unit && unit._onNewInput) {
      unit._onNewInput(this);
    }
  }
Send output to a p5.js-sound, Web Audio Node, or use signal to
 control an AudioParam

 @method connect
 @for p5.Effect
 @param {Object} unit