.  The intial and final
      // automation values are pretty arbitrary, except that they should be such
      // that the panner and listener produces non-constant output.
      const listenerParams = [
        {name: 'positionX', initial: [1, 0], final: [1000, 1]},
        {name: 'positionY', initial: [1, 0], final: [1000, 1]},
        {name: 'positionZ', initial: [1, 0], final: [1000, 1]},
        {name: 'forwardX', initial: [-1, 0], final: [1, 1]},
        {name: 'forwardY', initial: [-1, 0], final: [1,