使AudioNode输出连接到多个AudioParam,并将多个AudioNode输出连接到单个 AudioParam,同时多次调用connect()。因此支持Fan-in and fan-out。
 AudioParam可以从连接到它的任何AudioNode输出获取渲染的音频数据,并通过下混合将其转换为单声道(如果本身不是单声道的话)。然后,它将其他这样的输出和固定参数混合( AudioParam的值通常没有任何连接),包括为参数调度的任何时间的变化。


var lfo = audioCtx.createOscillator();
lfo.frequency.value = 2.0; // Hz, two times per second

var lfoGain = audioCtx.createGain();
lfoGain.gain.value = 0.5;

// this is the parameter that is going to be modulated
var gain = audioCtx.createGain();
gain.gain.value = 0.5;

// Oscillators go from -1 to 1
// Make it go from -0.5 to +0.5 by connecting it to a GainNode with a gain value of 0.5

// because the value of the gain.gain AudioParam is originaly 0.5, the value is added, and it will go from 0.0 to 1.0


Note: There can only be one connection between an output from one specific AudioNode and an AudioParam. Multiple connections to the same termini are equivalent to a single such connection (the duplicates are ignored).




In this example, we will be altering the gain value of a GainNode using an OscillatorNode with a slow frequency value. This technique is know as an LFO-controlled parameter.

var AudioContext = window.AudioContext || window.webkitAudioContext;

var audioCtx = new AudioContext();

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

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

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

// create a gain whose gain AudioParam will be controlled by the LFO
var 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

// connect the oscillator that will produce audio to the gain

// connect the gain to the destination so we hear sound

// start the oscillator that will produce audio

// start the oscillator that will modify the gain value


The AudioParam you are connecting to.
Output (optional)
An index describing which output of the current AudioNode you want to connect to the AudioParam. The index numbers are defined according to the number of output channels (see Audio channels.)  If this parameter is out-of-bound, an INDEX_SIZE_ERR exception is thrown.


Specification Status Comment
Web Audio API
Working Draft  

Browser compatibility

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help! (en-US)
Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
connect(AudioParam) (Yes) webkit (en-US) (Yes) 未实现 (Yes) 未实现
Feature Android Firefox Mobile (Gecko) Firefox OS (Gecko) IE Phone Opera Mobile Safari Mobile
connect(AudioParam) 未实现 (Yes) (Yes) 未实现 未实现 未实现

See also