diff --git a/include/STTypes.h b/include/STTypes.h
index 09ccad6..3767f76 100644
--- a/include/STTypes.h
+++ b/include/STTypes.h
@@ -87,14 +87,16 @@ namespace soundtouch
  
  #endif
 
-    /// Define this to allow CPU-specific assembler optimizations. Notice that 
-    /// having this enabled on non-x86 platforms doesn't matter; the compiler can 
-    /// drop unsupported extensions on different platforms automatically. 
-    /// However, if you're having difficulties getting the optimized routines 
-    /// compiled with your compler (e.g. some gcc compiler versions may be picky), 
-    /// you may wish to disable the optimizations to make the library compile.
-    #define ALLOW_OPTIMIZATIONS     1
+    #if (WIN32 || __i386__ || __x86_64__)
+        /// Define this to allow X86-specific assembler/intrinsic optimizations. 
+        /// Notice that library contains also usual C++ versions of each of these
+        /// these routines, so if you're having difficulties getting the optimized 
+        /// routines compiled for whatever reason, you may disable these optimizations 
+        /// to make the library compile.
 
+        #define ALLOW_X86_OPTIMIZATIONS     1
+
+    #endif
 
     // If defined, allows the SIMD-optimized routines to take minor shortcuts 
     // for improved performance. Undefine to require faithfully similar SIMD 
@@ -113,11 +115,9 @@ namespace soundtouch
             #error "conflicting sample types defined"
         #endif // FLOAT_SAMPLES
 
-        #ifdef ALLOW_OPTIMIZATIONS
-            #if (WIN32 || __i386__ || __x86_64__)
-                // Allow MMX optimizations
-                #define ALLOW_MMX   1
-            #endif
+        #ifdef ALLOW_X86_OPTIMIZATIONS
+            // Allow MMX optimizations
+            #define ALLOW_MMX   1
         #endif
 
     #else
@@ -127,15 +127,13 @@ namespace soundtouch
         // data type for sample accumulation: Use double to utilize full precision.
         typedef double LONG_SAMPLETYPE;
 
-        #ifdef ALLOW_OPTIMIZATIONS
+        #ifdef ALLOW_X86_OPTIMIZATIONS
                 // Allow 3DNow! and SSE optimizations
             #if WIN32
                 #define ALLOW_3DNOW     1
             #endif
 
-            #if (WIN32 || __i386__ || __x86_64__)
-                #define ALLOW_SSE       1
-            #endif
+            #define ALLOW_SSE       1
         #endif
 
     #endif  // INTEGER_SAMPLES
diff --git a/source/SoundTouch/cpu_detect_x86_gcc.cpp b/source/SoundTouch/cpu_detect_x86_gcc.cpp
index 54b1910..2c797dc 100644
--- a/source/SoundTouch/cpu_detect_x86_gcc.cpp
+++ b/source/SoundTouch/cpu_detect_x86_gcc.cpp
@@ -43,6 +43,7 @@
 #include <stdexcept>
 #include <string>
 #include "cpu_detect.h"
+#include "STTypes.h"
 
 #ifndef __GNUC__
 #error wrong platform - this source code file is for the GNU C compiler.
@@ -72,8 +73,10 @@ void disableExtensions(uint dwDisableMask)
 /// Checks which instruction set extensions are supported by the CPU.
 uint detectCPUextensions(void)
 {
-#ifndef __i386__
+#ifndef ALLOW_X86_OPTIMIZATIONS
+
     return 0; // always disable extensions on non-x86 platforms.
+
 #else
     uint res = 0;