knee(knee, time) {
    var t = time || 0;
    if (typeof knee === 'number') {
      this.compressor.knee.value = knee;
      this.compressor.knee.cancelScheduledValues(
        this.ac.currentTime + 0.01 + t
      );
      this.compressor.knee.linearRampToValueAtTime(
        knee,
        this.ac.currentTime + 0.02 + t
      );
    } else if (typeof knee !== 'undefined') {
      knee.connect(this.compressor.knee);
    }
    return this.compressor.knee.value;
  }
Get current knee or set value w/ time ramp

@method knee
@for p5.Compressor
@param {Number} [knee] A decibel value representing the range above the
                       threshold where the curve smoothly transitions to the "ratio" portion.
                       default = 30, range 0 - 40
@param {Number} [time]  Assign time value to schedule the change in value