AudioNode: connect() 方法

connect(destination)
connect(destination, outputIndex)
connect(destination, outputIndex, inputIndex)

const audioCtx = new AudioContext();

const oscillator = audioCtx.createOscillator();
const gainNode = audioCtx.createGain();

oscillator.connect(gainNode);
gainNode.connect(audioCtx.destination);

const audioCtx = new AudioContext();

// create an normal oscillator to make sound
const oscillator = audioCtx.createOscillator();

// create a second oscillator that will be used as an LFO (Low-frequency
// oscillator), and will control a parameter
const lfo = audioCtx.createOscillator();

// set the frequency of the second oscillator to a low number
lfo.frequency.value = 2.0; // 2Hz: two oscillations per second

// create a gain whose gain AudioParam will be controlled by the LFO
const gain = audioCtx.createGain();

// connect the LFO to the gain AudioParam. This means the value of the LFO
// will not produce any audio, but will change the value of the gain instead
lfo.connect(gain.gain);

// connect the oscillator that will produce audio to the gain
oscillator.connect(gain);

// connect the gain to the destination so we hear sound
gain.connect(audioCtx.destination);

// start the oscillator that will produce audio
oscillator.start();

// start the oscillator that will modify the gain value
lfo.start();