message: type coersion
diff: @@ -64,8 +64,8 @@ export class TickSource<Type extends BPM | Hertz> extends ToneWithContext<TickSo
  static getDefaults(): TickSourceOptions {
  return Object.assign({
  frequency: 1,
  - units: "hertz",
  - }, ToneWithContext.getDefaults()) as TickSourceOptions;
  + units: "hertz" as "hertz",
  + }, ToneWithContext.getDefaults());
  }
  /**
  