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                <p>Haz clic para iniciar el oscilador.</p>


p{text-align:center; line-height:100vh; white-space: nowrap;}


                var audioCtx = new (window.AudioContext || window.webkitAudioContext)();

// crea un oscilador
var oscilador  = audioCtx.createOscillator();
// establece la frecuencia de oscilación en hertzios
oscilador.frequency.value = 250;
// establece el tipo de oscilador
// puede tomar uno de estos valores: "sine", "square", "sawtooth", "triangle" y "custom".
// el valor por defecto es "sine".
oscilador.type = "triangle";
// conecta el oscilador con con su destino ( altavoces, auriculares . . . etc )

addEventListener("click", function(){
  // inicia el oscilador
  // para el oscilator despues de 3 segundos
  oscilador.stop(audioCtx.currentTime + 3);
  // al acabarse la oscilación sacamos un mensaje en consola
  oscilador.onended = function(){console.log("Y por fin el silencio")};
  // cuando el oscilador se detiene utilizando el método stop(), ya no puede ser reiniciado.