diff --git a/src/sdl/emulator/SdlSpeaker.cpp b/src/sdl/emulator/SdlSpeaker.cpp
index 57bb2b5..e2c2dc6 100644
--- a/src/sdl/emulator/SdlSpeaker.cpp
+++ b/src/sdl/emulator/SdlSpeaker.cpp
@@ -1,7 +1,7 @@
 #include "SdlSpeaker.h"
 
 #include <iostream>
-#include <math.h>
+#include <cmath>
 #include <valarray>
 #include <vector>