var meter = createAudioMeter(audioContext,clipLevel,averaging,clipLag);
audioContext: the AudioContext you're using.
clipLevel: the level (0 to 1) that you would consider "clipping". Defaults to 0.98.
averaging: how "smoothed" you would like the meter to be over time. Should be between 0 and less than 1. Defaults to 0.95.
clipLag: how long you would like the "clipping" indicator to show after clipping has occured, in milliseconds. Defaults to 750ms.
meter.checkClipping();
returns true if the node has clipped in the last clipLag milliseconds.
meter.shutdown();
used to destroy the node (it's important to disconnect and remove the event handler for any ScriptProcessor).