diff --git a/index.html b/index.html
index 0c03762..1f37b0d 100644
--- a/index.html
+++ b/index.html
@@ -79,6 +79,10 @@
         <button onclick="setPreset('0.333,0.5,0.666')">二對三</button>
         <button onclick="setPreset('0.58')">有點 Swing</button>
     </div>
+    <div class="preset-buttons">
+        <button onclick="setPreset('')">清除</button>
+    </div>
+
 
     <script type="text/javascript">
     let audioContext = null;