Master volume.

import { AudioProvider, useTone, useVolume } from "@webaudio-kit/react";

function MasterVolumeDemo() {
  const volume = useVolume();
  const tone = useTone({ frequency: 440, gain: 0.12 });

  return (
    <>
      <input
        max={0.5}
        min={0}
        onChange={(event) => void volume.setGain(event.currentTarget.valueAsNumber)}
        step={0.01}
        type="range"
        value={volume.gain}
      />
      <button onClick={() => void tone.play({ durationMs: 700 })}>
        Play volume reference
      </button>
    </>
  );
}

export function App() {
  return (
    <AudioProvider>
      <MasterVolumeDemo />
    </AudioProvider>
  );
}