diff --git a/src/sound/oplsynth/nukedopl3.cpp b/src/sound/oplsynth/nukedopl3.cpp
index c99c5c55ba..990418cd8b 100644
--- a/src/sound/oplsynth/nukedopl3.cpp
+++ b/src/sound/oplsynth/nukedopl3.cpp
@@ -62,6 +62,9 @@
 // Envelope generator
 //
 
+namespace OPL3
+{
+
 typedef Bit16s(*envelope_sinfunc)(Bit16u phase, Bit16u envelope);
 typedef void(*envelope_genfunc)(opl_slot *slott);
 
@@ -1017,6 +1020,8 @@ NukedOPL3::NukedOPL3(bool stereo) {
 	Reset();
 }
 
+} // namespace OPL3
+
 OPLEmul *NukedOPL3Create(bool stereo) {
-	return new NukedOPL3(stereo);
+	return new OPL3::NukedOPL3(stereo);
 }
diff --git a/src/sound/oplsynth/nukedopl3.h b/src/sound/oplsynth/nukedopl3.h
index 3c3c65895a..76f34dcda0 100644
--- a/src/sound/oplsynth/nukedopl3.h
+++ b/src/sound/oplsynth/nukedopl3.h
@@ -32,6 +32,9 @@
 #include "opl.h"
 #include "musicblock.h"
 
+namespace OPL3
+{
+
 typedef uintptr_t	Bitu;
 typedef intptr_t	Bits;
 typedef uint32_t	Bit32u;
@@ -233,3 +236,5 @@ public:
 
 	NukedOPL3(bool stereo);
 };
+
+} // namespace OPL3