mult(num) {
    var mult = new Mult(num);
    sigChain(this.mathOps, mult, Mult, this.oscillator, this.output);
    return this;
  }
Multiply the p5.Oscillator's output amplitude
 by a fixed value (i.e. turn it up!). Calling this method
 again will override the initial mult() with a new value.

 @method  mult
 @for p5.Oscillator
 @param {Number} number Constant number to multiply
 @return {p5.Oscillator} Oscillator Returns this oscillator
                                    with multiplied output