---
title: AudioParamDescriptor
slug: Web/API/AudioParamDescriptor
translation_of: Web/API/AudioParamDescriptor
---
<div>{{APIRef("Web Audio API")}}</div>

<p><span class="seoSummary">The <code><strong>AudioParamDescriptor</strong></code> dictionary of the <a href="/en-US/docs/Web/API/Web_Audio_API">Web Audio API</a> specifies properties for an {{domxref("AudioParam")}} objects.</span> It is used to create custom <code>AudioParam</code>s on an {{domxref("AudioWorkletNode")}}. If the underlying {{domxref("AudioWorkletProcessor")}} has a {{domxref("AudioWorkletProcessor.parameterDescriptors", "parameterDescriptors")}} static getter, then the returned array of objects based on this dictionary is used internally by <code>AudioWorkletNode</code> constructor to populate its {{domxref("AudioWorkletNode.parameters", "parameters")}} property accordingly.</p>

<h2 id="属性">属性</h2>

<dl>
 <dt><code>name</code></dt>
 <dd>The {{domxref("DOMString")}} which represents the name of the <code>AudioParam</code>. Under this name the <code>AudioParam</code> will be available in the {{domxref("AudioWorkletNode.parameters", "parameters")}} property of the node, and under this name the {{domxref("AudioWorkletProcessor.process")}} method will acquire the calculated values of this <code>AudioParam</code>.</dd>
 <dt><code>automationRate</code> {{optional_inline}}</dt>
 <dd>Either <code><a href="/en-US/docs/Web/API/AudioParam#a-rate">"a-rate"</a></code>, or <code><a href="/en-US/docs/Web/API/AudioParam#k-rate">"k-rate"</a></code> string which represents an automation rate of this <code>AudioParam</code>. Defaults to <code>"a-rate"</code>.</dd>
 <dt><code>minValue</code> {{optional_inline}}</dt>
 <dd>A <code>float</code> which represents minimum value of the <code>AudioParam</code>. Defaults to <code>-3.4028235e38</code>.</dd>
 <dt><code>maxValue</code> {{optional_inline}}</dt>
 <dd>A <code>float</code> which represents maximum value of the <code>AudioParam</code>. Defaults to <code>3.4028235e38</code>.</dd>
 <dt><code>defaultValue</code> {{optional_inline}}</dt>
 <dd>A <code>float</code> which represents initial value of the <code>AudioParam</code>. Defaults to <code>0</code>.</dd>
</dl>

<h2 id="例子">例子</h2>

<p>{{page("/en-US/docs/Web/API/AudioWorkletNode/parameters", "Examples")}}</p>

<h2 id="规范">规范</h2>

<table class="standard-table">
 <tbody>
  <tr>
   <th scope="col">Specification</th>
   <th scope="col">Status</th>
   <th scope="col">Comment</th>
  </tr>
  <tr>
   <td>{{SpecName('Web Audio API','#dictdef-audioparamdescriptor','AudioParamDescriptor')}}</td>
   <td>{{Spec2('Web Audio API')}}</td>
   <td>Initial definition.</td>
  </tr>
 </tbody>
</table>

<h2 id="浏览器兼容性">浏览器兼容性</h2>



<p>{{Compat("api.AudioParamDescriptor")}}</p>