diff --git a/src/sfizz/OnePoleFilter.h b/src/sfizz/OnePoleFilter.h
index 72c71c3e..9c3afd0f 100644
--- a/src/sfizz/OnePoleFilter.h
+++ b/src/sfizz/OnePoleFilter.h
@@ -29,6 +29,12 @@
 
 namespace sfz
 {
+/**
+ * @brief An implementation of a one pole filter. This is a scalar
+ * implementation.
+ *
+ * @tparam Type the underlying type of the filter.
+ */
 template <class Type = float>
 class OnePoleFilter {
 public:
@@ -137,4 +143,4 @@ private:
         state += 2 * intermediate;
     }
 };
-}
\ No newline at end of file
+}