message: detune can be passed into the options object
diff: @@ -11,6 +11,7 @@ type onSilenceCallback = (instrument: Monophonic<any>) => void;
  export interface MonophonicOptions extends InstrumentOptions {
  portamento: Seconds;
  onsilence: onSilenceCallback;
  + detune: Cents;
  }
  /**
  @@ -55,6 +56,7 @@ export abstract class Monophonic<Options extends MonophonicOptions> extends Inst
  static getDefaults(): MonophonicOptions {
  return Object.assign(Instrument.getDefaults(), {
  + detune: 0,
  onsilence: noOp,
  portamento: 0,
  });
  