diff --git a/effect_modulated_delay.cpp b/effect_modulated_delay.cpp
index afb3697..94195a4 100644
--- a/effect_modulated_delay.cpp
+++ b/effect_modulated_delay.cpp
@@ -1,4 +1,4 @@
-/* Audio Library for Teensy 3.X
+/* 
    Copyright (c) 2014, Pete (El Supremo)
    Copyright (c) 2019, Holger Wirtz
 
diff --git a/effect_modulated_delay.h b/effect_modulated_delay.h
index 85ed2a8..00eda8b 100644
--- a/effect_modulated_delay.h
+++ b/effect_modulated_delay.h
@@ -1,4 +1,4 @@
-/* Audio Library for Teensy 3.X
+/* 
    Copyright (c) 2014, Pete (El Supremo)
    Copyright (c) 2019, Holger Wirtz
 
diff --git a/effect_stereo_mono.cpp b/effect_stereo_mono.cpp
index 8eb9067..119142e 100644
--- a/effect_stereo_mono.cpp
+++ b/effect_stereo_mono.cpp
@@ -1,4 +1,4 @@
-/* Audio Library for Teensy 3.X
+/* 
    Copyright (c) 2019, Holger Wirtz
 
    Permission is hereby granted, free of charge, to any person obtaining a copy
diff --git a/effect_stereo_mono.h b/effect_stereo_mono.h
index f9b39f9..059e59e 100644
--- a/effect_stereo_mono.h
+++ b/effect_stereo_mono.h
@@ -1,4 +1,4 @@
-/* Audio Library for Teensy 3.X
+/* 
    Copyright (c) 2019, Holger Wirtz
 
    Permission is hereby granted, free of charge, to any person obtaining a copy
@@ -27,7 +27,7 @@
 #include "AudioStream.h"
 
 /*************************************************************************/
-//                A u d i o E f f e c t M o d u l a t e d D e l a y
+//                A u d i o E f f e c t S t e r e o M o n o
 // Written by Holger Wirtz
 // 20191023 - inital version
 
diff --git a/mono2stereo.cpp b/mono2stereo.cpp
new file mode 100644
index 0000000..41b18e9
--- /dev/null
+++ b/mono2stereo.cpp
@@ -0,0 +1,69 @@
+/*
+   Copyright (c) 2019, Holger Wirtz
+
+   Permission is hereby granted, free of charge, to any person obtaining a copy
+   of this software and associated documentation files (the "Software"), to deal
+   in the Software without restriction, including without limitation the rights
+   to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+   copies of the Software, and to permit persons to whom the Software is
+   furnished to do so, subject to the following conditions:
+
+   The above copyright notice and this permission notice shall be included in
+   all copies or substantial portions of the Software.
+
+   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+   AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+   LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+   THE SOFTWARE.
+*/
+
+#include <Arduino.h>
+#include <Audio.h>
+#include "mono2stereo.h"
+
+/*************************************************************************/
+//                A u d i o E f f e c t M o n o  2 S t e r e o
+// Written by Holger Wirtz
+// 20191122 - inital version
+
+void Mono2Stereo::update(void)
+{
+  audio_block_t *in;
+  audio_block_t *out[2];
+
+  in = receiveReadOnly(0);
+  out[0] = allocate();
+  out[1] = allocate();
+
+  if (in && out[0] && out[1])
+  {
+    int16_t *ip = in->data;
+    int16_t *op[2] = { out[0]->data, out[1]->data };
+    float f_l = _pseudo_log * sinf(_pan * PI / 2); // _Pan [L0.0 ... M0.5 ... 1.0R]
+    float f_r = _pseudo_log * cosf(_pan * PI / 2);
+
+    for (uint16_t i = 0; i < AUDIO_BLOCK_SAMPLES; i++)
+    {
+      *op[0] = int16_t(f_l * (*ip));
+      *op[1] = int16_t(f_r * (*ip++));
+      op[0]++;
+      op[1]++;
+    }
+
+    if (in)
+    {
+      release(in);
+    }
+    for (uint8_t i = 0; i < 2; i++)
+    {
+      if (out[i])
+      {
+        transmit(out[i], i);
+        release(out[i]);
+      }
+    }
+  }
+}
diff --git a/mono2stereo.h b/mono2stereo.h
new file mode 100644
index 0000000..fd2ba97
--- /dev/null
+++ b/mono2stereo.h
@@ -0,0 +1,52 @@
+/*
+   Copyright (c) 2019, Holger Wirtz
+
+   Permission is hereby granted, free of charge, to any person obtaining a copy
+   of this software and associated documentation files (the "Software"), to deal
+   in the Software without restriction, including without limitation the rights
+   to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+   copies of the Software, and to permit persons to whom the Software is
+   furnished to do so, subject to the following conditions:
+
+   The above copyright notice and this permission notice shall be included in
+   all copies or substantial portions of the Software.
+
+   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+   AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+   LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+   THE SOFTWARE.
+*/
+
+#ifndef mono2stereo_h_
+#define mono2stereo_h_
+
+#include "Arduino.h"
+#include "AudioStream.h"
+
+/*************************************************************************/
+//                A u d i o E f f e c t M o n o  2 S t e r e o
+// Written by Holger Wirtz
+// 20191122 - inital version
+
+class Mono2Stereo : public AudioStream
+{
+  public:
+    Mono2Stereo(void):
+      AudioStream(1, inputQueueArray)
+    {
+      _pan = 0.5;
+    }
+
+    virtual void update(void);
+
+  private:
+    audio_block_t *inputQueueArray[4];
+    audio_block_t *out[2];
+    const float _pseudo_log = 1048575 / (float)(1 << 20);
+    float _pan;
+};
+
+#endif