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 # 2020年 福岡女学院大学 「サウンド・デザイン」第1回
 
+講義音声(約1時間)を聞いてください。講義の中にはスマートフォンを使って音を収録してみるレッスンが含まれています。
+
 ## 講義音声
 
 <figure>
@@ -14,7 +16,7 @@ weight: 3
         controls preload="metadata" 
          style="width:100%;">
         <source src="/docs/2020/fukujo-sounddesign/class-1/sounddesign-1.opus">
-        <source src="/docs/2020/fukujo-sounddesign/class-1/sounddesign-1.aac">
+        <source src="/docs/2020/fukujo-sounddesign/class-1/sounddesign-1_fixed.m4a">
 
             Your browser does not support the
             <code>audio</code> element.
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         controls preload="metadata" 
          style="width:100%;">
         <source src="/docs/2020/fukujo-sounddesign/class-1/sounddesign-1.opus">
-        <source src="/docs/2020/fukujo-sounddesign/class-1/sounddesign-1.aac">
+        <source src="/docs/2020/fukujo-sounddesign/class-1/sounddesign-1_fixed.m4a">
             Your browser does not support the
             <code>audio</code> element.
     </audio>
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