diff --git a/src/SoundMaker/Sounds/MonauralMixer.cs b/src/SoundMaker/Sounds/MonauralMixer.cs
index 32c3149..528c9a2 100644
--- a/src/SoundMaker/Sounds/MonauralMixer.cs
+++ b/src/SoundMaker/Sounds/MonauralMixer.cs
@@ -22,7 +22,7 @@ public MonauralMixer(IReadOnlyList<ISoundChannel> channels) : base(channels)
     /// <returns>the mixed wave of monaural. モノラルの波形データ : MonauralWave</returns>
     public MonauralWave Mix()
     {
-        var result = Enumerable.Repeat((ushort)0, GetMaxWaveLength()).ToArray();
+        var result = Enumerable.Repeat((short)0, GetMaxWaveLength()).ToArray();
         _ = Parallel.ForEach(Channels, channel =>
         {
             var waveNumericData = channel.GenerateWave();
@@ -30,7 +30,7 @@ public MonauralWave Mix()
             {
                 for (var i = 0; i < waveNumericData.Length; i++)
                 {
-                    result[i] += (ushort)(waveNumericData[i] / Channels.Count);
+                    result[i] += (short)(waveNumericData[i] / Channels.Count);
                 }
             }
         });
diff --git a/src/SoundMaker/Sounds/MonauralWave.cs b/src/SoundMaker/Sounds/MonauralWave.cs
index ffd1860..ad3c2f4 100644
--- a/src/SoundMaker/Sounds/MonauralWave.cs
+++ b/src/SoundMaker/Sounds/MonauralWave.cs
@@ -8,18 +8,18 @@ public class MonauralWave : IWave
     /// constructor. コンストラクタ
     /// </summary>
     /// <param name="wave">the collection of wave data. 波形データを表す配列</param>
-    public MonauralWave(IReadOnlyCollection<ushort> wave)
+    public MonauralWave(IReadOnlyCollection<short> wave)
     {
         var argumentIntegers = wave.ToArray();
-        OriginalVolumeWave = new ushort[wave.Count];
-        Wave = new ushort[wave.Count];
+        OriginalVolumeWave = new short[wave.Count];
+        Wave = new short[wave.Count];
         Array.Copy(argumentIntegers, OriginalVolumeWave, argumentIntegers.Length);
         Array.Copy(argumentIntegers, Wave, argumentIntegers.Length);
     }
 
-    private ushort[] OriginalVolumeWave { get; set; }
+    private short[] OriginalVolumeWave { get; set; }
 
-    private ushort[] Wave { get; set; }
+    private short[] Wave { get; set; }
 
     public int Volume { get; private set; } = 100;
 
@@ -37,7 +37,7 @@ public void ChangeVolume(int volume)
         Volume = volume;
         for (var i = 0; i < Wave.Length; i++)
         {
-            Wave[i] = (ushort)(Wave[i] * (volume / 100d));
+            Wave[i] = (short)(Wave[i] * (volume / 100d));
         }
     }
 
@@ -48,7 +48,7 @@ public void ChangeVolume(int volume)
     public void Append(MonauralWave wave)
     {
         Wave = Wave.Concat(wave.GetWave()).ToArray();
-        OriginalVolumeWave = new ushort[Wave.Length];
+        OriginalVolumeWave = new short[Wave.Length];
         Array.Copy(Wave, OriginalVolumeWave, Wave.Length);
     }
 
@@ -59,7 +59,7 @@ public byte[] GetBytes(BitRateType bitRate)
             var result = new List<byte>(Wave.Length * 2);
             foreach (var value in Wave)
             {
-                var bytes = BitConverter.GetBytes((short)((value - short.MaxValue) / 2));
+                var bytes = BitConverter.GetBytes(value);
                 result.Add(bytes[0]);
                 result.Add(bytes[1]);
             }
@@ -70,7 +70,7 @@ public byte[] GetBytes(BitRateType bitRate)
             var result = new List<byte>(Wave.Length);
             foreach (var value in Wave)
             {
-                result.Add((byte)(value / 256));
+                result.Add((byte)(value / 256 + 128));
             }
             return result.ToArray();
         }
@@ -79,10 +79,10 @@ public byte[] GetBytes(BitRateType bitRate)
     /// <summary>
     /// get the wave. 音の波形データを取得するメソッド。
     /// </summary>
-    /// <returns>the wave. 波形データ : unsigned short[]</returns>
-    public ushort[] GetWave()
+    /// <returns>the wave. 波形データ : short[]</returns>
+    public short[] GetWave()
     {
-        var result = new ushort[Wave.Length];
+        var result = new short[Wave.Length];
         Array.Copy(Wave, result, Wave.Length);
         return result;
     }
diff --git a/src/SoundMaker/Sounds/Score/BasicSoundComponentBase.cs b/src/SoundMaker/Sounds/Score/BasicSoundComponentBase.cs
index 9fbbb32..785645e 100644
--- a/src/SoundMaker/Sounds/Score/BasicSoundComponentBase.cs
+++ b/src/SoundMaker/Sounds/Score/BasicSoundComponentBase.cs
@@ -27,9 +27,9 @@ public BasicSoundComponentBase(LengthType length, bool isDotted)
     /// </summary>
     public bool IsDotted { get; }
 
-    public abstract ushort[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType);
+    public abstract short[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType);
 
-    public abstract ushort[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType);
+    public abstract short[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType);
 
     public int GetWaveArrayLength(SoundFormat format, int tempo)
     {
diff --git a/src/SoundMaker/Sounds/Score/ISoundComponent.cs b/src/SoundMaker/Sounds/Score/ISoundComponent.cs
index c4789d1..bb576bd 100644
--- a/src/SoundMaker/Sounds/Score/ISoundComponent.cs
+++ b/src/SoundMaker/Sounds/Score/ISoundComponent.cs
@@ -23,10 +23,10 @@ public interface ISoundComponent
     /// <param name="tempo">quarter note/rest per minute. 一分間の四分音符・休符の数</param>
     /// <param name="length">length of the array. 配列の長さ</param>
     /// <param name="waveType">type of wave.波形の種類</param>
-    /// <returns>data of wave. 波形データ : unsigned short[]</returns>
+    /// <returns>data of wave. 波形データ :  short[]</returns>
     /// <exception cref="ArgumentOutOfRangeException">Tempo must be non-negative and greater than 0.</exception>
     /// <exception cref="ArgumentOutOfRangeException">Length must be non-negative.</exception>
-    ushort[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType);
+    short[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType);
 
     /// <summary>
     /// generate the wave of wave type. 波形の種類に基づいて波形データの配列を生成するメソッド。
@@ -34,7 +34,7 @@ public interface ISoundComponent
     /// <param name="format">format of the sound.音のフォーマット</param>
     /// <param name="tempo">quarter note/rest per minute. 一分間の四分音符・休符の数</param>
     /// <param name="waveType">type of wave.波形の種類</param>
-    /// <returns>data of wave. 波形データ : unsigned short[]</returns>
+    /// <returns>data of wave. 波形データ :  short[]</returns>
     /// <exception cref="ArgumentOutOfRangeException">Tempo must be non-negative and greater than 0.</exception>
-    ushort[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType);
+    short[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType);
 }
diff --git a/src/SoundMaker/Sounds/Score/Note.cs b/src/SoundMaker/Sounds/Score/Note.cs
index 4313a22..aa9815c 100644
--- a/src/SoundMaker/Sounds/Score/Note.cs
+++ b/src/SoundMaker/Sounds/Score/Note.cs
@@ -82,12 +82,12 @@ private static void CheckArgument(Scale scale, int scaleNumber)
         }
     }
 
-    public override ushort[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType)
+    public override short[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType)
     {
         return waveType.GenerateWave(format, length, Volume, Hertz);
     }
 
-    public override ushort[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType)
+    public override short[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType)
     {
         var length = GetWaveArrayLength(format, tempo);
         return GenerateWave(format, tempo, length, waveType);
diff --git a/src/SoundMaker/Sounds/Score/Rest.cs b/src/SoundMaker/Sounds/Score/Rest.cs
index 60d4bca..3af7480 100644
--- a/src/SoundMaker/Sounds/Score/Rest.cs
+++ b/src/SoundMaker/Sounds/Score/Rest.cs
@@ -14,12 +14,12 @@ public class Rest : BasicSoundComponentBase
     public Rest(LengthType length, bool isDotted = false)
         : base(length, isDotted) { }
 
-    public override ushort[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType)
+    public override short[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType)
     {
         return GetWave(format, tempo, length);
     }
 
-    public override ushort[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType)
+    public override short[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType)
     {
         return GetWave(format, tempo);
     }
@@ -29,8 +29,8 @@ public override ushort[] GenerateWave(SoundFormat format, int tempo, WaveTypeBas
     /// </summary>
     /// <param name="format">format of the sound.音のフォーマット</param>
     /// <param name="tempo">一分間の休符の数</param>
-    /// <returns>0埋めされた配列 : unsigned short[]</returns>
-    private ushort[] GetWave(SoundFormat format, int tempo)
+    /// <returns>0埋めされた配列 :  short[]</returns>
+    private short[] GetWave(SoundFormat format, int tempo)
     {
         var length = GetWaveArrayLength(format, tempo);
         return GetWave(format, tempo, length);
@@ -42,9 +42,9 @@ private ushort[] GetWave(SoundFormat format, int tempo)
     /// <param name="format">format of the sound.音のフォーマット</param>
     /// <param name="tempo">一分間の休符の数</param>
     /// <param name="length">length of the array. 配列の長さ</param>
-    /// <returns>0埋めされた配列 : unsigned short[]</returns>
-    private ushort[] GetWave(SoundFormat format, int tempo, int length)
+    /// <returns>0埋めされた配列 :  short[]</returns>
+    private short[] GetWave(SoundFormat format, int tempo, int length)
     {
-        return Enumerable.Repeat<ushort>(0, length).ToArray();
+        return Enumerable.Repeat<short>(0, length).ToArray();
     }
 }
diff --git a/src/SoundMaker/Sounds/Score/Tie.cs b/src/SoundMaker/Sounds/Score/Tie.cs
index 467629e..9d3d7e4 100644
--- a/src/SoundMaker/Sounds/Score/Tie.cs
+++ b/src/SoundMaker/Sounds/Score/Tie.cs
@@ -47,12 +47,12 @@ public Tie(Note baseNote, IReadOnlyCollection<Note> additionalNotes)
     /// </summary>
     public IReadOnlyCollection<Note> AdditionalNotes { get; }
 
-    public ushort[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType)
+    public short[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType)
     {
         return BaseNote.GenerateWave(format, tempo, length, waveType);
     }
 
-    public ushort[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType)
+    public short[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType)
     {
         var length = GetWaveArrayLength(format, tempo);
         return GenerateWave(format, tempo, length, waveType);
diff --git a/src/SoundMaker/Sounds/Score/Tuplet.cs b/src/SoundMaker/Sounds/Score/Tuplet.cs
index 7dd1b18..d7e45b5 100644
--- a/src/SoundMaker/Sounds/Score/Tuplet.cs
+++ b/src/SoundMaker/Sounds/Score/Tuplet.cs
@@ -54,9 +54,9 @@ public int GetWaveArrayLength(SoundFormat format, int tempo)
         return SoundWaveLengthCalclator.Calclate(format, tempo, Length, IsDotted);
     }
 
-    public ushort[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType)
+    public short[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType)
     {
-        var result = new List<ushort>(length);
+        var result = new List<short>(length);
         // 一個あたりの配列の長さを算出
         var count = GetLengthPerOneComponent();
         int i;
@@ -74,7 +74,7 @@ public ushort[] GenerateWave(SoundFormat format, int tempo, int length, WaveType
         return result.ToArray();
     }
 
-    public ushort[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType)
+    public short[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType)
     {
         var length = GetWaveArrayLength(format, tempo);
         return GenerateWave(format, tempo, length, waveType);
diff --git a/src/SoundMaker/Sounds/SoundChannels/ISoundChannel.cs b/src/SoundMaker/Sounds/SoundChannels/ISoundChannel.cs
index 1275b08..5d1a85d 100644
--- a/src/SoundMaker/Sounds/SoundChannels/ISoundChannel.cs
+++ b/src/SoundMaker/Sounds/SoundChannels/ISoundChannel.cs
@@ -43,8 +43,8 @@ public interface ISoundChannel : IEnumerable<ISoundComponent>
     /// <summary>
     /// generate wave data. 音の波形データを生成するメソッド。
     /// </summary>
-    /// <returns>the array of wave data.音の波形データの配列 : unsigned short[]</returns>
-    ushort[] GenerateWave();
+    /// <returns>the array of wave data.音の波形データの配列 :  short[]</returns>
+    short[] GenerateWave();
 
     /// <summary>
     /// add sound component to this. サウンドコンポーネントを追加するメソッド。
diff --git a/src/SoundMaker/Sounds/SoundChannels/LowBitNoiseSoundChannel.cs b/src/SoundMaker/Sounds/SoundChannels/LowBitNoiseSoundChannel.cs
index 88de65f..5952578 100644
--- a/src/SoundMaker/Sounds/SoundChannels/LowBitNoiseSoundChannel.cs
+++ b/src/SoundMaker/Sounds/SoundChannels/LowBitNoiseSoundChannel.cs
@@ -29,9 +29,9 @@ public LowBitNoiseSoundChannel(int tempo, SoundFormat format, PanType panType) :
     {
     }
 
-    public override ushort[] GenerateWave()
+    public override short[] GenerateWave()
     {
-        var result = new List<ushort>();
+        var result = new List<short>();
         foreach (var soundComponent in SoundComponents)
         {
             result.AddRange(soundComponent.GenerateWave(Format, Tempo, new LowBitNoiseWave()));
diff --git a/src/SoundMaker/Sounds/SoundChannels/PseudoTriangleSoundChannel.cs b/src/SoundMaker/Sounds/SoundChannels/PseudoTriangleSoundChannel.cs
index 9a1c925..d42589b 100644
--- a/src/SoundMaker/Sounds/SoundChannels/PseudoTriangleSoundChannel.cs
+++ b/src/SoundMaker/Sounds/SoundChannels/PseudoTriangleSoundChannel.cs
@@ -27,9 +27,9 @@ public PseudoTriangleSoundChannel(int tempo, SoundFormat format, PanType panType
     {
     }
 
-    public override ushort[] GenerateWave()
+    public override short[] GenerateWave()
     {
-        var result = new List<ushort>();
+        var result = new List<short>();
         foreach (var soundComponent in SoundComponents)
         {
             var wave = soundComponent.GenerateWave(Format, Tempo, new PseudoTriangleWave());
diff --git a/src/SoundMaker/Sounds/SoundChannels/SoundChannelBase.cs b/src/SoundMaker/Sounds/SoundChannels/SoundChannelBase.cs
index 7d11e4d..0dbbd8b 100644
--- a/src/SoundMaker/Sounds/SoundChannels/SoundChannelBase.cs
+++ b/src/SoundMaker/Sounds/SoundChannels/SoundChannelBase.cs
@@ -117,18 +117,19 @@ public void Import(IEnumerable<ISoundComponent> components)
         WaveArrayLength = components.Sum(component => component.GetWaveArrayLength(Format, Tempo));
     }
 
-    public abstract ushort[] GenerateWave();
+    public abstract short[] GenerateWave();
 
-    protected void FadeInOut(ushort[] wave)
+    protected void FadeInOut(short[] wave)
     {
         var tenMSCount = (int)((double)Format.SamplingFrequency * 0.01);
         if (wave.Length > tenMSCount << 1)
         {
             for (int i = 0; i < tenMSCount; i++)
             {
-                double magnification = (1.0 / tenMSCount) * (i + 1);
-                wave[i] = (ushort)(((short)(wave[i] - short.MaxValue - 1) * magnification) + short.MaxValue + 1);
-                wave[wave.Length - i - 1] = (ushort)(((short)(wave[wave.Length - i - 1] - short.MaxValue - 1) * magnification) + short.MaxValue + 1);
+                double fadeMagnification = (1.0 / tenMSCount) * (i + 1);
+
+                wave[i] = (short)(fadeMagnification * wave[i]);
+                wave[wave.Length - i - 1] = (short)(fadeMagnification * wave[wave.Length - i - 1]);
             }
         }
     }
diff --git a/src/SoundMaker/Sounds/SoundChannels/SquareSoundChannel.cs b/src/SoundMaker/Sounds/SoundChannels/SquareSoundChannel.cs
index c53b89d..ee185a3 100644
--- a/src/SoundMaker/Sounds/SoundChannels/SquareSoundChannel.cs
+++ b/src/SoundMaker/Sounds/SoundChannels/SquareSoundChannel.cs
@@ -40,9 +40,9 @@ public SquareSoundChannel(int tempo, SoundFormat format, SquareWaveRatio ratio,
     /// </summary>
     private SquareWaveRatio Ratio { get; }
 
-    public override ushort[] GenerateWave()
+    public override short[] GenerateWave()
     {
-        var result = new List<ushort>();
+        var result = new List<short>();
         foreach (var soundComponent in SoundComponents)
         {
             var wave = soundComponent.GenerateWave(Format, Tempo, new SquareWave(Ratio));
diff --git a/src/SoundMaker/Sounds/SoundChannels/TriangleSoundChannel.cs b/src/SoundMaker/Sounds/SoundChannels/TriangleSoundChannel.cs
index 9fa068a..44a07c0 100644
--- a/src/SoundMaker/Sounds/SoundChannels/TriangleSoundChannel.cs
+++ b/src/SoundMaker/Sounds/SoundChannels/TriangleSoundChannel.cs
@@ -26,9 +26,9 @@ public TriangleSoundChannel(int tempo, SoundFormat format, PanType panType, int
     /// <exception cref="ArgumentOutOfRangeException">Tempo must be non-negative and greater than 0.</exception>
     public TriangleSoundChannel(int tempo, SoundFormat format, PanType panType) : base(tempo, format, panType) { }
 
-    public override ushort[] GenerateWave()
+    public override short[] GenerateWave()
     {
-        var result = new List<ushort>();
+        var result = new List<short>();
         foreach (var soundComponent in SoundComponents)
         {
             var wave = soundComponent.GenerateWave(Format, Tempo, new TriangleWave());
diff --git a/src/SoundMaker/Sounds/StereoMixer.cs b/src/SoundMaker/Sounds/StereoMixer.cs
index 15d8446..5603b53 100644
--- a/src/SoundMaker/Sounds/StereoMixer.cs
+++ b/src/SoundMaker/Sounds/StereoMixer.cs
@@ -26,15 +26,15 @@ public StereoWave Mix()
     {
         var max = GetMaxWaveLength();
         var channelCount = GetChannelCount();
-        var rightResult = Enumerable.Repeat((ushort)0, max).ToArray();
-        var leftResult = Enumerable.Repeat((ushort)0, max).ToArray();
+        var rightResult = Enumerable.Repeat((short)0, max).ToArray();
+        var leftResult = Enumerable.Repeat((short)0, max).ToArray();
         _ = Parallel.ForEach(Channels, channel =>
         {
             Merge(leftResult, rightResult, channel, channelCount);
         });
         return new StereoWave(rightResult, leftResult);
     }
-    private void Merge(ushort[] left, ushort[] right, ISoundChannel channel, ChannelCount channelCount)
+    private void Merge(short[] left, short[] right, ISoundChannel channel, ChannelCount channelCount)
     {
         var waveNumericData = channel.GenerateWave();
         if (channel.PanType is PanType.Left)
@@ -43,7 +43,7 @@ private void Merge(ushort[] left, ushort[] right, ISoundChannel channel, Channel
             {
                 for (var i = 0; i < waveNumericData.Length; i++)
                 {
-                    left[i] += (ushort)(waveNumericData[i] / channelCount.Left);
+                    left[i] += (short)(waveNumericData[i] / channelCount.Left);
                 }
             }
         }
@@ -53,7 +53,7 @@ private void Merge(ushort[] left, ushort[] right, ISoundChannel channel, Channel
             {
                 for (var i = 0; i < waveNumericData.Length; i++)
                 {
-                    right[i] += (ushort)(waveNumericData[i] / channelCount.Right);
+                    right[i] += (short)(waveNumericData[i] / channelCount.Right);
                 }
             }
         }
@@ -66,8 +66,8 @@ private void Merge(ushort[] left, ushort[] right, ISoundChannel channel, Channel
                 {
                     for (var i = 0; i < waveNumericData.Length; i++)
                     {
-                        right[i] += (ushort)(waveNumericData[i] / channelCount.Right);
-                        left[i] += (ushort)(waveNumericData[i] / channelCount.Left);
+                        right[i] += (short)(waveNumericData[i] / channelCount.Right);
+                        left[i] += (short)(waveNumericData[i] / channelCount.Left);
                     }
                 }
             }
diff --git a/src/SoundMaker/Sounds/StereoWave.cs b/src/SoundMaker/Sounds/StereoWave.cs
index e7b46b0..9c1ce5b 100644
--- a/src/SoundMaker/Sounds/StereoWave.cs
+++ b/src/SoundMaker/Sounds/StereoWave.cs
@@ -9,29 +9,29 @@ public class StereoWave : IWave
     /// </summary>
     /// <param name="rightWave">the wave of right. 右の波形データ</param>
     /// <param name="leftWave">the wave of left. 左の波形データ</param>
-    public StereoWave(IReadOnlyCollection<ushort> rightWave, IReadOnlyCollection<ushort> leftWave)
+    public StereoWave(IReadOnlyCollection<short> rightWave, IReadOnlyCollection<short> leftWave)
     {
         var rightArgument = rightWave.ToArray();
         var leftArgument = leftWave.ToArray();
 
-        RightOriginalVolumeWave = new ushort[rightWave.Count];
-        LeftOriginalVolumeWave = new ushort[leftWave.Count];
+        RightOriginalVolumeWave = new short[rightWave.Count];
+        LeftOriginalVolumeWave = new short[leftWave.Count];
         Array.Copy(rightArgument, RightOriginalVolumeWave, rightArgument.Length);
         Array.Copy(leftArgument, LeftOriginalVolumeWave, leftArgument.Length);
 
-        RightWave = new ushort[rightWave.Count];
-        LeftWave = new ushort[leftWave.Count];
+        RightWave = new short[rightWave.Count];
+        LeftWave = new short[leftWave.Count];
         Array.Copy(rightArgument, RightWave, rightArgument.Length);
         Array.Copy(leftArgument, LeftWave, leftArgument.Length);
     }
 
-    private ushort[] RightOriginalVolumeWave { get; set; }
+    private short[] RightOriginalVolumeWave { get; set; }
 
-    private ushort[] LeftOriginalVolumeWave { get; set; }
+    private short[] LeftOriginalVolumeWave { get; set; }
 
-    private ushort[] RightWave { get; set; }
+    private short[] RightWave { get; set; }
 
-    private ushort[] LeftWave { get; set; }
+    private short[] LeftWave { get; set; }
 
     /// <summary>
     /// volume of the wave. 波形データの音量
@@ -60,14 +60,14 @@ public void ChangeVolume(int volume, SoundDirectionType channelType)
             case SoundDirectionType.Left:
                 for (var i = 0; i < LeftWave.Length; i++)
                 {
-                    LeftWave[i] = (ushort)(LeftOriginalVolumeWave[i] * (volume / 100d));
+                    LeftWave[i] = (short)(LeftOriginalVolumeWave[i] * (volume / 100d));
                 }
                 LeftVolume = volume;
                 break;
             case SoundDirectionType.Right:
                 for (var i = 0; i < RightWave.Length; i++)
                 {
-                    RightWave[i] = (ushort)(RightOriginalVolumeWave[i] * (volume / 100d));
+                    RightWave[i] = (short)(RightOriginalVolumeWave[i] * (volume / 100d));
                 }
                 RightVolume = volume;
                 break;
@@ -75,8 +75,8 @@ public void ChangeVolume(int volume, SoundDirectionType channelType)
                 var maxAndMinLength = GetMaxAndMinWaveLength();
                 for (var i = 0; i < maxAndMinLength.Min; i++)
                 {
-                    RightWave[i] = (ushort)(RightOriginalVolumeWave[i] * (volume / 100d));
-                    LeftWave[i] = (ushort)(LeftOriginalVolumeWave[i] * (volume / 100d));
+                    RightWave[i] = (short)(RightOriginalVolumeWave[i] * (volume / 100d));
+                    LeftWave[i] = (short)(LeftOriginalVolumeWave[i] * (volume / 100d));
                 }
 
                 // 残りを処理する。
@@ -85,7 +85,7 @@ public void ChangeVolume(int volume, SoundDirectionType channelType)
                     RightOriginalVolumeWave : LeftOriginalVolumeWave;
                 for (var i = maxAndMinLength.Min; i < maxAndMinLength.Max; i++)
                 {
-                    wave[i] = (ushort)(originalWave[i] * (volume / 100d));
+                    wave[i] = (short)(originalWave[i] * (volume / 100d));
                 }
                 RightVolume = volume;
                 LeftVolume = volume;
@@ -114,15 +114,15 @@ private List<byte> Get8BitBytes()
         for (var i = 0; i < maxAndMinLength.Min; i++)
         {
             // Point : ステレオの波は左右左右左右左右・・・・・・左右
-            resultWave.Add((byte)(LeftWave[i] / 256));
-            resultWave.Add((byte)(RightWave[i] / 256));
+            resultWave.Add((byte)(LeftWave[i] / 256 + 128));
+            resultWave.Add((byte)(RightWave[i] / 256 + 128));
         }
         // 追加しきれていない波形データを追加する
         if (LeftWave.Length == maxAndMinLength.Max)
         {
             for (var i = maxAndMinLength.Min; i < maxAndMinLength.Max; i++)
             {
-                resultWave.Add((byte)(LeftWave[i] / 256));
+                resultWave.Add((byte)(LeftWave[i] / 256 + 128));
                 resultWave.Add(0);
             }
         }
@@ -131,7 +131,7 @@ private List<byte> Get8BitBytes()
             for (var i = maxAndMinLength.Min; i < maxAndMinLength.Max; i++)
             {
                 resultWave.Add(0);
-                resultWave.Add((byte)(RightWave[i] / 256));
+                resultWave.Add((byte)(RightWave[i] / 256 + 128));
             }
         }
         return resultWave;
@@ -147,10 +147,8 @@ private List<byte> Get16BitBytes()
         var resultWave = new List<byte>(maxAndMinLength.Max * 4);
         for (var i = 0; i < maxAndMinLength.Min; i++)
         {
-            var left = LeftWave[i] == ushort.MaxValue ?
-                (short)(LeftWave[i] - short.MaxValue - 1) : (short)(LeftWave[i] - short.MaxValue);
-            var right = RightWave[i] == ushort.MaxValue ?
-                (short)(RightWave[i] - short.MaxValue - 1) : (short)(RightWave[i] - short.MaxValue);
+            var left = LeftWave[i];
+            var right = RightWave[i];
             var leftBytes = BitConverter.GetBytes(left);
             var rightBytes = BitConverter.GetBytes(right);
             // Point : ステレオの波は左右左右左右左右・・・・・・左右
@@ -164,8 +162,7 @@ private List<byte> Get16BitBytes()
         {
             for (var i = maxAndMinLength.Min; i < maxAndMinLength.Max; i++)
             {
-                var left = LeftWave[i] == ushort.MaxValue ?
-                (short)(LeftWave[i] - short.MaxValue - 1) : (short)(LeftWave[i] - short.MaxValue);
+                var left = LeftWave[i];
                 var leftBytes = BitConverter.GetBytes(left);
                 resultWave.Add(leftBytes[0]);
                 resultWave.Add(leftBytes[1]);
@@ -177,8 +174,7 @@ private List<byte> Get16BitBytes()
         {
             for (var i = maxAndMinLength.Min; i < maxAndMinLength.Max; i += 2)
             {
-                var right = RightWave[i] == ushort.MaxValue ?
-                    (short)(RightWave[i] - short.MaxValue - 1) : (short)(RightWave[i] - short.MaxValue);
+                var right = RightWave[i];
                 var rightBytes = BitConverter.GetBytes(right);
                 resultWave.Add(0);
                 resultWave.Add(0);
@@ -192,23 +188,23 @@ private List<byte> Get16BitBytes()
     /// <summary>
     /// get the wave on the right. 右側のチャンネルの音の波形データを取得するメソッド。
     /// </summary>
-    /// <returns>the wave on the right. 右側のチャンネルの音の波形データ : unsigned short[]</returns>
-    public ushort[] GetRightWave()
+    /// <returns>the wave on the right. 右側のチャンネルの音の波形データ :  short[]</returns>
+    public short[] GetRightWave()
     {
-        var resultushorts = new ushort[RightWave.Length];
-        Array.Copy(RightWave, resultushorts, RightWave.Length);
-        return resultushorts;
+        var resultshorts = new short[RightWave.Length];
+        Array.Copy(RightWave, resultshorts, RightWave.Length);
+        return resultshorts;
     }
 
     /// <summary>
     /// get the wave on the left. 左側のチャンネルの音の波形データを取得するメソッド。
     /// </summary>
-    /// <returns>the wave on the left. 左側のチャンネルの音の波形データ : unsigned short[]</returns>
-    public ushort[] GetLeftWave()
+    /// <returns>the wave on the left. 左側のチャンネルの音の波形データ :  short[]</returns>
+    public short[] GetLeftWave()
     {
-        var resultushorts = new ushort[LeftWave.Length];
-        Array.Copy(LeftWave, resultushorts, LeftWave.Length);
-        return resultushorts;
+        var resultshorts = new short[LeftWave.Length];
+        Array.Copy(LeftWave, resultshorts, LeftWave.Length);
+        return resultshorts;
     }
 
     /// <summary>
@@ -218,11 +214,11 @@ public ushort[] GetLeftWave()
     public void Append(StereoWave wave)
     {
         RightWave = RightWave.Concat(wave.GetRightWave()).ToArray();
-        RightOriginalVolumeWave = new ushort[RightWave.Length];
+        RightOriginalVolumeWave = new short[RightWave.Length];
         Array.Copy(RightWave, RightOriginalVolumeWave, RightWave.Length);
 
         LeftWave = LeftWave.Concat(wave.GetLeftWave()).ToArray();
-        LeftOriginalVolumeWave = new ushort[LeftWave.Length];
+        LeftOriginalVolumeWave = new short[LeftWave.Length];
         Array.Copy(LeftWave, LeftOriginalVolumeWave, LeftWave.Length);
     }
 
diff --git a/src/SoundMaker/Sounds/WaveTypes/LowBitNoiseWave.cs b/src/SoundMaker/Sounds/WaveTypes/LowBitNoiseWave.cs
index 6e5719a..76905a7 100644
--- a/src/SoundMaker/Sounds/WaveTypes/LowBitNoiseWave.cs
+++ b/src/SoundMaker/Sounds/WaveTypes/LowBitNoiseWave.cs
@@ -5,31 +5,31 @@
 public class LowBitNoiseWave : WaveTypeBase
 {
     [Obsolete("Use 'GenerateWave(SoundFormat format, int length, int volume, double hertz)'")]
-    public override ushort[] GenerateWave(SoundFormat format, int tempo, int length, int volume, double hertz)
+    public override short[] GenerateWave(SoundFormat format, int tempo, int length, int volume, double hertz)
     {
         CheckGenerateWaveArgs(tempo, length, volume, hertz);
         return GenerateWave(format, length, volume, hertz);
     }
 
-    public override ushort[] GenerateWave(SoundFormat format, int length, int volume, double hertz)
+    public override short[] GenerateWave(SoundFormat format, int length, int volume, double hertz)
     {
-        var result = new List<ushort>(length);
+        var result = new List<short>(length);
         var mode = false;
         var count = 1;
         while (count <= length)
         {
             var allRepeatTimes = (int)((int)format.SamplingFrequency / hertz);
             var firstRepeatTimes = (int)(allRepeatTimes * 0.5);
-            var height = (ushort)new Random().Next(0, ushort.MaxValue + 1);
+            var height = (short)new Random().Next(short.MinValue, short.MaxValue + 1);
             for (var i = 1; i <= firstRepeatTimes && mode && count <= length; i++, count++)
             {
-                var sound = (ushort)(height * volume / 100);
+                var sound = (short)(height * volume / 100);
                 result.Add(sound);
             }
-            height = (ushort)new Random().Next(0, ushort.MaxValue + 1);
+            height = (short)new Random().Next(short.MinValue, short.MaxValue + 1);
             for (var i = 1; i <= allRepeatTimes - firstRepeatTimes && !mode && count <= length; i++, count++)
             {
-                var sound = (ushort)(height * volume / 100);
+                var sound = (short)(height * volume / 100);
                 result.Add(sound);
             }
             mode = !mode;
diff --git a/src/SoundMaker/Sounds/WaveTypes/PseudoTriangleWave.cs b/src/SoundMaker/Sounds/WaveTypes/PseudoTriangleWave.cs
index 0bcd3d3..b3ed276 100644
--- a/src/SoundMaker/Sounds/WaveTypes/PseudoTriangleWave.cs
+++ b/src/SoundMaker/Sounds/WaveTypes/PseudoTriangleWave.cs
@@ -4,14 +4,23 @@
 /// </summary>
 public class PseudoTriangleWave : WaveTypeBase
 {
+    private static readonly short[] _leftHeights = new short[]
+    {
+        0, -4096, -8192, -12288, -16384, -20480, -24576, -28672, -28672, -24576, -20480, -16384, -12288, -8192, -4096, 0,
+    };
+    private static readonly short[] _rightHeights = new short[]
+    {
+        4095, 8191, 12287, 16383, 20479, 24575, 28671, short.MaxValue, short.MaxValue, 28671, 24575, 20479, 16383, 12287, 8191, 4095
+    };
+
     [Obsolete("Use 'GenerateWave(SoundFormat format, int length, int volume, double hertz)'")]
-    public override ushort[] GenerateWave(SoundFormat format, int tempo, int length, int volume, double hertz)
+    public override short[] GenerateWave(SoundFormat format, int tempo, int length, int volume, double hertz)
     {
         CheckGenerateWaveArgs(tempo, length, volume, hertz);
         return GenerateWave(format, length, volume, hertz);
     }
 
-    public override ushort[] GenerateWave(SoundFormat format, int length, int volume, double hertz)
+    public override short[] GenerateWave(SoundFormat format, int length, int volume, double hertz)
     {
         CheckGenerateWaveArgs(length, volume, hertz);
 
@@ -23,7 +32,7 @@ public override ushort[] GenerateWave(SoundFormat format, int length, int volume
             return new TriangleWave().GenerateWave(format, length, volume, hertz);
         }
 
-        var result = new List<ushort>(length);
+        var result = new List<short>(length);
         var unitWave = GenerateUnitWave(format, volume, hertz);
         for (var i = 0; i < length / unitWave.Count; i++)
         {
@@ -36,53 +45,40 @@ public override ushort[] GenerateWave(SoundFormat format, int length, int volume
         return result.ToArray();
     }
 
-    private List<ushort> GenerateUnitWave(SoundFormat format, int volume, double hertz)
+    private List<short> GenerateUnitWave(SoundFormat format, int volume, double hertz)
     {
         var repeatNumber = (int)((int)format.SamplingFrequency / hertz);
-        // なぜか配列よりリストの方が早い
-        var result = new List<ushort>(repeatNumber);
+
+        var result = new short[repeatNumber];
+        var steps = 32;
         // 音量の倍率(1.00 ~ 0.00)
         var volumeMagnification = volume / 100d;
         // 階段の幅
-        var stairsWidth = repeatNumber / 32;
+        var stairsWidth = repeatNumber / steps;
         // 幅の余り
-        var r = repeatNumber % 32;
+        var r = repeatNumber % steps;
 
-        // 上り波形
-        for (var i = 0; i < 16; i++)
-        {
-            var sound = (ushort)(ushort.MaxValue * (i / 15d));
-            sound = (ushort)(sound * volumeMagnification);
-            for (var j = 0; j < stairsWidth; j++)
-            {
-                result.Add(sound);
-            }
-            // 余りがある場合は足す。波形の後ろ側の部分に足す
-            // ex. r = 31の場合、i = 1 ~ 15の時足す。
-            if (i <= r / 2 && i != 0)
-            {
-                result.Add(sound);
-            }
-        }
-        // 下り波形
-        // 下り波形では上り波形より数値を減らす
-        var negativeDiff = (ushort)(ushort.MaxValue * (1 / 30d));
-        for (var i = 15; i >= 0; i--)
+        int position = 0;
+        for (int i = 0; i < _leftHeights.Length; i++)
         {
-            var sound = (ushort)(ushort.MaxValue * (i / 15d));
-            sound = sound != 0 ? (ushort)(sound - negativeDiff) : sound;
-            sound = (ushort)(sound * volumeMagnification);
-            for (var j = 0; j < stairsWidth; j++)
+            var leftHeight = (short)(_leftHeights[i] * volumeMagnification);
+            var rightHeight = (short)(_rightHeights[i] * volumeMagnification);
+
+            for (int j = 0; j < stairsWidth; j++)
             {
-                result.Add(sound);
+                result[position] = leftHeight;
+                result[result.Length - 1 - position] = rightHeight;
+                position++;
             }
-            // 余りがある場合は足す。波形の後ろ側の部分に足す
-            // ex. r = 31の場合、i = 15 ~ 0の時足す。
-            if (i < (r / 2) + (r % 2))
+            if (r > 0)
             {
-                result.Add(sound);
+                result[position] = leftHeight;
+                result[result.Length - 1 - position] = rightHeight;
+                r -= 2;
+                position++;
             }
         }
-        return result;
+
+        return result.ToList();
     }
 }
diff --git a/src/SoundMaker/Sounds/WaveTypes/SquareWave.cs b/src/SoundMaker/Sounds/WaveTypes/SquareWave.cs
index 1bf0b9d..bf0f10c 100644
--- a/src/SoundMaker/Sounds/WaveTypes/SquareWave.cs
+++ b/src/SoundMaker/Sounds/WaveTypes/SquareWave.cs
@@ -28,15 +28,15 @@ public SquareWave(SquareWaveRatio squareWaveRatio)
     };
 
     [Obsolete("Use 'GenerateWave(SoundFormat format, int length, int volume, double hertz)'")]
-    public override ushort[] GenerateWave(SoundFormat format, int tempo, int length, int volume, double hertz)
+    public override short[] GenerateWave(SoundFormat format, int tempo, int length, int volume, double hertz)
     {
         CheckGenerateWaveArgs(tempo, length, volume, hertz);
         return GenerateWave(format, length, volume, hertz);
     }
 
-    public override ushort[] GenerateWave(SoundFormat format, int length, int volume, double hertz)
+    public override short[] GenerateWave(SoundFormat format, int length, int volume, double hertz)
     {
-        var result = new List<ushort>(length);
+        var result = new List<short>(length);
         var unitWave = GenerateUnitWave(format, volume, hertz);
         for (var i = 0; i < length / unitWave.Count; i++)
         {
@@ -49,24 +49,26 @@ public override ushort[] GenerateWave(SoundFormat format, int length, int volume
         return result.ToArray();
     }
 
-    private List<ushort> GenerateUnitWave(SoundFormat format, int volume, double hertz)
+    private List<short> GenerateUnitWave(SoundFormat format, int volume, double hertz)
     {
         var ratioIndex = (int)SquareWaveRatio;
         var allRepeatTimes = (int)((int)format.SamplingFrequency / hertz);
         var firstRepeatTimes = (int)(allRepeatTimes * Ratio[ratioIndex].Item1);
         // なぜか配列よりリストの方が早い
-        var result = new List<ushort>(allRepeatTimes);
+        var result = new List<short>(allRepeatTimes);
         // 音量の倍率(1.00 ~ 0.00)
         var volumeMagnification = volume / 100d;
 
+        var top = (short)(short.MaxValue * volumeMagnification);
+        var bottom = (short)(-top);
+
         for (var i = 0; i < firstRepeatTimes; i++)
         {
-            result.Add(0);
+            result.Add(top);
         }
         for (var i = 0; i < allRepeatTimes - firstRepeatTimes; i++)
         {
-            var sound = (ushort)(ushort.MaxValue * volumeMagnification);
-            result.Add(sound);
+            result.Add(bottom);
         }
         return result;
     }
diff --git a/src/SoundMaker/Sounds/WaveTypes/TriangleWave.cs b/src/SoundMaker/Sounds/WaveTypes/TriangleWave.cs
index 898b0e7..38e72c3 100644
--- a/src/SoundMaker/Sounds/WaveTypes/TriangleWave.cs
+++ b/src/SoundMaker/Sounds/WaveTypes/TriangleWave.cs
@@ -5,16 +5,16 @@
 public class TriangleWave : WaveTypeBase
 {
     [Obsolete("Use 'GenerateWave(SoundFormat format, int length, int volume, double hertz)'")]
-    public override ushort[] GenerateWave(SoundFormat format, int tempo, int length, int volume, double hertz)
+    public override short[] GenerateWave(SoundFormat format, int tempo, int length, int volume, double hertz)
     {
         CheckGenerateWaveArgs(tempo, length, volume, hertz);
         return GenerateWave(format, length, volume, hertz);
     }
 
-    public override ushort[] GenerateWave(SoundFormat format, int length, int volume, double hertz)
+    public override short[] GenerateWave(SoundFormat format, int length, int volume, double hertz)
     {
         CheckGenerateWaveArgs(length, volume, hertz);
-        var result = new List<ushort>(length);
+        var result = new List<short>(length);
         var unitWave = GenerateUnitWave(format, volume, hertz);
         for (var i = 0; i < length / unitWave.Count; i++)
         {
@@ -27,31 +27,39 @@ public override ushort[] GenerateWave(SoundFormat format, int length, int volume
         return result.ToArray();
     }
 
-    private List<ushort> GenerateUnitWave(SoundFormat format, int volume, double hertz)
+    private List<short> GenerateUnitWave(SoundFormat format, int volume, double hertz)
     {
-        var repeatNumber = (int)format.SamplingFrequency / hertz;
-        // なぜか配列よりリストの方が早い
-        var result = new List<ushort>((int)repeatNumber);
-        // 直線の方程式の傾きを求める。
-        var slope = ushort.MaxValue / (repeatNumber / 2);
-        // 音量の倍率(1.00 ~ 0.00)
-        var volumeMagnification = volume / 100d;
+        var repeatNumber = (int)((int)format.SamplingFrequency / hertz);
+
+        var result = new short[repeatNumber];
+
+
+        var halfCount = repeatNumber >> 1;
+        var quarterCount = halfCount >> 1;
+
+        var slope = ushort.MaxValue / halfCount;
 
-        // 傾き正波形
-        for (var i = 1; i <= repeatNumber / 2; i++)
+        var volumeMagnification = volume / 100d;
+        // halfCount基準で中央のオフセット(lengthが奇数の場合1)
+        var midOffsetFromHalfCount = repeatNumber % 2;
+        for (int i = 0; i < quarterCount; i++)
         {
-            var sound = (ushort)(slope * i);
-            sound = (ushort)(sound * volumeMagnification);
-            result.Add(sound);
+            var sound = (short)(0 + slope * (i + 1));
+            sound = (short)(sound * volumeMagnification);
+            result[i] = sound;
+            result[halfCount - i - 1] = sound;
+
+            var negativeSound = (short)(-sound);
+            result[result.Length - i - 1] = negativeSound;
+            result[halfCount + i + midOffsetFromHalfCount] = negativeSound;
         }
-        // 傾き負波形
-        slope = -slope;
-        for (var i = (int)((repeatNumber / 2) + 1); i <= repeatNumber; i++)
+
+        if (halfCount % 2 != 0)
         {
-            var sound = (ushort)(ushort.MaxValue + (slope * i));
-            sound = (ushort)(sound * volumeMagnification);
-            result.Add(sound);
+            result[quarterCount] = short.MaxValue;
+            result[halfCount + quarterCount + midOffsetFromHalfCount] = short.MinValue;
         }
-        return result;
+
+        return result.ToList();
     }
 }
diff --git a/src/SoundMaker/Sounds/WaveTypes/WaveTypeBase.cs b/src/SoundMaker/Sounds/WaveTypes/WaveTypeBase.cs
index aa62bc0..e168dd3 100644
--- a/src/SoundMaker/Sounds/WaveTypes/WaveTypeBase.cs
+++ b/src/SoundMaker/Sounds/WaveTypes/WaveTypeBase.cs
@@ -12,13 +12,13 @@ public abstract class WaveTypeBase
     /// <param name="length">length of the array. 配列の長さ</param>
     /// <param name="volume">volume 音量（0 ~ 100）</param>
     /// <param name="hertz">hertz of the sound. 音の周波数</param>
-    /// <returns>the array of wave data. : unsigned short[]</returns>
+    /// <returns>the array of wave data. :  short[]</returns>
     /// <exception cref="ArgumentOutOfRangeException">Tempo must be non-negative and greater than 0.</exception>
     /// <exception cref="ArgumentOutOfRangeException">Length must be non-negative.</exception>
     /// <exception cref="ArgumentOutOfRangeException">Hertz must be non-negative and greater than 0.</exception>
     /// <exception cref="ArgumentOutOfRangeException">Volume must be below than 100 and more than 0.</exception>
     [Obsolete("Use 'GenerateWave(SoundFormat format, int length, int volume, double hertz)'")]
-    public abstract ushort[] GenerateWave(SoundFormat format, int tempo, int length, int volume, double hertz);
+    public abstract short[] GenerateWave(SoundFormat format, int tempo, int length, int volume, double hertz);
 
     /// <summary>
     /// generate array of wave data. 波形データの配列を生成する。
@@ -27,11 +27,11 @@ public abstract class WaveTypeBase
     /// <param name="length">length of the array. 配列の長さ</param>
     /// <param name="volume">volume 音量（0 ~ 100）</param>
     /// <param name="hertz">hertz of the sound. 音の周波数</param>
-    /// <returns>the array of wave data. : unsigned short[]</returns>
+    /// <returns>the array of wave data. :  short[]</returns>
     /// <exception cref="ArgumentOutOfRangeException">Length must be non-negative.</exception>
     /// <exception cref="ArgumentOutOfRangeException">Hertz must be non-negative and greater than 0.</exception>
     /// <exception cref="ArgumentOutOfRangeException">Volume must be below than 100 and more than 0.</exception>
-    public abstract ushort[] GenerateWave(SoundFormat format, int length, int volume, double hertz);
+    public abstract short[] GenerateWave(SoundFormat format, int length, int volume, double hertz);
 
     [Obsolete("Use 'CheckGenerateWaveArgs(int length, int volume, double hertz)'")]
     protected void CheckGenerateWaveArgs(int tempo, int length, int volume, double hertz)
diff --git a/test/UnitTests/Sounds/MonauralWaveTest.cs b/test/UnitTests/Sounds/MonauralWaveTest.cs
index 1f0a0fa..ad4dd14 100644
--- a/test/UnitTests/Sounds/MonauralWaveTest.cs
+++ b/test/UnitTests/Sounds/MonauralWaveTest.cs
@@ -14,7 +14,7 @@ public MonauralWaveTest(ITestOutputHelper output)
     [Fact(DisplayName = "ボリュームの大きさが正しく反映されているかのテスト。ボリュームは0から100の間の整数値")]
     public void TestReflectedVolume()
     {
-        var wave = GetTestMonauralWave(defaultWaveValue: ushort.MinValue, waveLength: 100);
+        var wave = GetTestMonauralWave(defaultWaveValue: short.MinValue, waveLength: 100);
         wave.ChangeVolume(-1);
         // -1になってたらやばい
         Assert.Equal(0, wave.Volume);
@@ -30,7 +30,7 @@ public void TestReflectedVolume()
     [Fact(DisplayName = "波形のボリュームが変更されるかのテスト")]
     public void TestChangeVolume()
     {
-        var defaultWaveValue = ushort.MaxValue;
+        var defaultWaveValue = short.MaxValue;
         var wave = GetTestMonauralWave(defaultWaveValue: defaultWaveValue, waveLength: 100);
         // 音量を二分の一にする。波形データの値も半分になるはず。
         var volume = 50;
@@ -39,7 +39,7 @@ public void TestChangeVolume()
 
         Output.WriteLine("ボリューム: 50");
         Output.WriteLine("波形をテストする。");
-        WaveAssert.Equal((ushort)(defaultWaveValue * volumeMultiplier), wave.GetWave());
+        WaveAssert.Equal((short)(defaultWaveValue * volumeMultiplier), wave.GetWave());
     }
 
     [Fact(DisplayName = "生成したバイト列の長さを正しく取得できるかをテストする。")]
@@ -57,8 +57,8 @@ public void TestGetLengthOfBytes()
     [Fact(DisplayName = "二つの同じ長さの波形が正しく追加されているかをテストする。")]
     public void TestAppendWave()
     {
-        var monauralWave1 = GetTestMonauralWave(defaultWaveValue: ushort.MinValue, waveLength: 100);
-        var monauralWave2 = GetTestMonauralWave(defaultWaveValue: ushort.MaxValue, waveLength: 100);
+        var monauralWave1 = GetTestMonauralWave(defaultWaveValue: short.MinValue, waveLength: 100);
+        var monauralWave2 = GetTestMonauralWave(defaultWaveValue: short.MaxValue, waveLength: 100);
         // 16bitの場合
         var bitRate = BitRateType.SixteenBit;
         // 期待する長さを計算する。
@@ -73,12 +73,12 @@ public void TestAppendWave()
         Assert.Equal(monauralWave1.GetLengthOfBytes(BitRateType.SixteenBit), lengthOf16bit);
         Assert.Equal(monauralWave1.GetLengthOfBytes(BitRateType.EightBit), lengthOf8bit);
 
-        // 末尾に追加されていることを確認する。先頭の値はusort.MinValue、末尾の値はushort.MaxValueになっているはず。
+        // 末尾に追加されていることを確認する。先頭の値はusort.MinValue、末尾の値はshort.MaxValueになっているはず。
         var wave = monauralWave1.GetWave();
-        Assert.True(wave[0] == ushort.MinValue && wave[^1] == ushort.MaxValue);
+        Assert.True(wave[0] == short.MinValue && wave[^1] == short.MaxValue);
     }
 
-    private MonauralWave GetTestMonauralWave(ushort defaultWaveValue, int waveLength)
+    private MonauralWave GetTestMonauralWave(short defaultWaveValue, int waveLength)
     {
         var rightWave = Enumerable.Repeat(defaultWaveValue, waveLength).ToArray();
         return new MonauralWave(rightWave);
diff --git a/test/UnitTests/Sounds/Score/TestTuplet.cs b/test/UnitTests/Sounds/Score/TestTuplet.cs
index c01bffd..7a85042 100644
--- a/test/UnitTests/Sounds/Score/TestTuplet.cs
+++ b/test/UnitTests/Sounds/Score/TestTuplet.cs
@@ -7,14 +7,14 @@ public class TestTuplet
 {
     private class SoundComponent : ISoundComponent
     {
-        public ushort[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType)
+        public short[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType)
         {
-            return new ushort[0];
+            return new short[0];
         }
 
-        public ushort[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType)
+        public short[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType)
         {
-            return new ushort[0];
+            return new short[0];
         }
 
         public int GetWaveArrayLength(SoundFormat format, int tempo)
diff --git a/test/UnitTests/Sounds/SoundChannels/TestSoundChannelBase.cs b/test/UnitTests/Sounds/SoundChannels/TestSoundChannelBase.cs
index 6140772..af1c42f 100644
--- a/test/UnitTests/Sounds/SoundChannels/TestSoundChannelBase.cs
+++ b/test/UnitTests/Sounds/SoundChannels/TestSoundChannelBase.cs
@@ -13,22 +13,22 @@ public SoundChannelBaseDerived(int tempo, SoundFormat format, PanType panType, i
         {
         }
 
-        public override ushort[] GenerateWave()
+        public override short[] GenerateWave()
         {
-            return new ushort[0];
+            return new short[0];
         }
     }
 
     private class SoundComponent : ISoundComponent
     {
-        public ushort[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType)
+        public short[] GenerateWave(SoundFormat format, int tempo, int length, WaveTypeBase waveType)
         {
-            return new ushort[0];
+            return new short[0];
         }
 
-        public ushort[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType)
+        public short[] GenerateWave(SoundFormat format, int tempo, WaveTypeBase waveType)
         {
-            return new ushort[0];
+            return new short[0];
         }
 
         public int GetWaveArrayLength(SoundFormat format, int tempo)
diff --git a/test/UnitTests/Sounds/StereoWaveTest.cs b/test/UnitTests/Sounds/StereoWaveTest.cs
index 1dabfd5..8385bbd 100644
--- a/test/UnitTests/Sounds/StereoWaveTest.cs
+++ b/test/UnitTests/Sounds/StereoWaveTest.cs
@@ -14,7 +14,7 @@ public StereoWaveTest(ITestOutputHelper output)
     [Fact(DisplayName = "ボリュームの大きさが正しく反映されているかのテスト。ボリュームは0から100の間の整数値")]
     public void TestReflectedVolume()
     {
-        var wave = GetTestStereoWave(defaultWaveValue: ushort.MinValue, leftWaveLength: 1, rightWaveLength: 100);
+        var wave = GetTestStereoWave(defaultWaveValue: short.MinValue, leftWaveLength: 1, rightWaveLength: 100);
         wave.ChangeVolume(-1, SoundDirectionType.Both);
         // 両方-1になってたらやばい
         Assert.Equal(0, wave.RightVolume);
@@ -34,7 +34,7 @@ public void TestReflectedVolume()
     [Fact(DisplayName = "ステレオ波形の左右両方のボリュームが変更されるかのテスト")]
     public void TestChangeVolumeBoth()
     {
-        var defaultWaveValue = ushort.MaxValue;
+        var defaultWaveValue = short.MaxValue;
         var wave = GetTestStereoWave(defaultWaveValue, 100, 100);
         // 音量を二分の一にする。波形データの値も半分になるはず。
         var volume = 50;
@@ -42,17 +42,17 @@ public void TestChangeVolumeBoth()
         wave.ChangeVolume(volume, SoundDirectionType.Both);
         Output.WriteLine("ボリューム: 50, 方向: 両方でテストする。");
         Output.WriteLine("右の波形をテストする。");
-        WaveAssert.Equal((ushort)(defaultWaveValue * volumeMultiplier), wave.GetRightWave());
+        WaveAssert.Equal((short)(defaultWaveValue * volumeMultiplier), wave.GetRightWave());
 
         Output.WriteLine("ボリューム: 50, 方向: 両方でテストする。");
         Output.WriteLine("左の波形をテストする。");
-        WaveAssert.Equal((ushort)(defaultWaveValue * volumeMultiplier), wave.GetLeftWave());
+        WaveAssert.Equal((short)(defaultWaveValue * volumeMultiplier), wave.GetLeftWave());
     }
 
     [Fact(DisplayName = "ステレオ波形の右のボリュームが変更されるかのテスト")]
     public void TestChangeVolumeRight()
     {
-        var defaultWaveValue = ushort.MaxValue;
+        var defaultWaveValue = short.MaxValue;
         var wave = GetTestStereoWave(defaultWaveValue, 100, 100);
         // 音量を二分の一にする。波形データの値も半分になるはず。
         var volume = 50;
@@ -60,7 +60,7 @@ public void TestChangeVolumeRight()
         wave.ChangeVolume(volume, SoundDirectionType.Right);
         Output.WriteLine("ボリューム: 50, 方向: 右でテストする。");
         Output.WriteLine("右の波形をテストする。");
-        WaveAssert.Equal((ushort)(defaultWaveValue * volumeMultiplier), wave.GetRightWave());
+        WaveAssert.Equal((short)(defaultWaveValue * volumeMultiplier), wave.GetRightWave());
 
         Output.WriteLine("ボリューム: 50, 方向: 右でテストする。");
         Output.WriteLine("左の波形をテストする。");
@@ -70,7 +70,7 @@ public void TestChangeVolumeRight()
     [Fact(DisplayName = "ステレオ波形の右のボリュームが変更されるかのテスト")]
     public void TestChangeVolumeLeft()
     {
-        var defaultWaveValue = ushort.MaxValue;
+        var defaultWaveValue = short.MaxValue;
         var wave = GetTestStereoWave(defaultWaveValue, 100, 100);
         // 音量を二分の一にする。波形データの値も半分になるはず。
         var volume = 50;
@@ -82,7 +82,7 @@ public void TestChangeVolumeLeft()
 
         Output.WriteLine("ボリューム: 50, 方向: 左でテストする。");
         Output.WriteLine("左の波形をテストする。");
-        WaveAssert.Equal((ushort)(defaultWaveValue * volumeMultiplier), wave.GetLeftWave());
+        WaveAssert.Equal((short)(defaultWaveValue * volumeMultiplier), wave.GetLeftWave());
     }
 
     [Fact(DisplayName = "生成したバイト列の長さを正しく取得できるかをテストする。")]
@@ -100,8 +100,8 @@ public void TestGetLengthOfBytes()
     [Fact(DisplayName = "二つの同じ長さの波形が正しく追加されているかをテストする。")]
     public void TestAppendWave()
     {
-        var stereoWave1 = GetTestStereoWave(defaultWaveValue: ushort.MinValue, leftWaveLength: 1, rightWaveLength: 100);
-        var stereoWave2 = GetTestStereoWave(defaultWaveValue: ushort.MaxValue, leftWaveLength: 1, rightWaveLength: 100);
+        var stereoWave1 = GetTestStereoWave(defaultWaveValue: short.MinValue, leftWaveLength: 1, rightWaveLength: 100);
+        var stereoWave2 = GetTestStereoWave(defaultWaveValue: short.MaxValue, leftWaveLength: 1, rightWaveLength: 100);
         // 16bitの場合
         var bitRate = BitRateType.SixteenBit;
         // 期待する長さを計算する。
@@ -116,17 +116,17 @@ public void TestAppendWave()
         Assert.Equal(stereoWave1.GetLengthOfBytes(BitRateType.SixteenBit), lengthOf16bit);
         Assert.Equal(stereoWave1.GetLengthOfBytes(BitRateType.EightBit), lengthOf8bit);
 
-        // 末尾に追加されていることを確認する。先頭の値はusort.MinValue、末尾の値はushort.MaxValueになっているはず。
+        // 末尾に追加されていることを確認する。先頭の値はusort.MinValue、末尾の値はshort.MaxValueになっているはず。
         var wave = stereoWave1.GetLeftWave();
-        Assert.True(wave[0] == ushort.MinValue && wave[^1] == ushort.MaxValue);
+        Assert.True(wave[0] == short.MinValue && wave[^1] == short.MaxValue);
         wave = stereoWave1.GetRightWave();
-        Assert.True(wave[0] == ushort.MinValue && wave[^1] == ushort.MaxValue);
+        Assert.True(wave[0] == short.MinValue && wave[^1] == short.MaxValue);
     }
 
-    private StereoWave GetTestStereoWave(ushort defaultWaveValue, int leftWaveLength, int rightWaveLength)
+    private StereoWave GetTestStereoWave(short defaultWaveValue, int leftWaveLength, int rightWaveLength)
     {
-        var rightWave = Enumerable.Repeat<ushort>(defaultWaveValue, rightWaveLength).ToArray();
-        var leftWave = Enumerable.Repeat<ushort>(defaultWaveValue, leftWaveLength).ToArray();
+        var rightWave = Enumerable.Repeat<short>(defaultWaveValue, rightWaveLength).ToArray();
+        var leftWave = Enumerable.Repeat<short>(defaultWaveValue, leftWaveLength).ToArray();
         return new StereoWave(rightWave, leftWave);
     }
 }
diff --git a/test/UnitTests/Sounds/WaveAssert.cs b/test/UnitTests/Sounds/WaveAssert.cs
index b587903..b9f1b46 100644
--- a/test/UnitTests/Sounds/WaveAssert.cs
+++ b/test/UnitTests/Sounds/WaveAssert.cs
@@ -1,7 +1,7 @@
 namespace SoundMakerTests.UnitTests.Sounds;
 internal static class WaveAssert
 {
-    public static void Equal(ushort waveValue, ushort[] targetWave)
+    public static void Equal(short waveValue, short[] targetWave)
     {
         foreach (var targetWaveValue in targetWave)
         {
diff --git a/test/UseCaseTests/CreateWaveFileTest.cs b/test/UseCaseTests/CreateWaveFileTest.cs
index 01828ac..5b40d02 100644
--- a/test/UseCaseTests/CreateWaveFileTest.cs
+++ b/test/UseCaseTests/CreateWaveFileTest.cs
@@ -127,7 +127,7 @@ public void ChangeVolume()
             GetStereo(SetAllScale(new PseudoTriangleSoundChannel(tempo, waveCase.SoundFormat, panType))),
             GetStereo(SetAllScale(new LowBitNoiseSoundChannel(tempo, waveCase.SoundFormat, panType)))
         };
-        var result = new StereoWave(new ushort[0], new ushort[0]);
+        var result = new StereoWave(new short[0], new short[0]);
         foreach (var wave in waves)
         {
             wave.ChangeVolume(1, SoundDirectionType.Both);