diff --git a/plugins/zynaddsubfx/ChangeLog b/plugins/zynaddsubfx/ChangeLog
index 0df66d70d..d0edbdc86 100644
--- a/plugins/zynaddsubfx/ChangeLog
+++ b/plugins/zynaddsubfx/ChangeLog
@@ -972,4 +972,5 @@
 10 Dec 2009 (Mark McCurry)
 	    - Separated out Presets and arrayed Presets to reduce warnings from
 	      the Wextra flag
+	    - Minor change to Filter_ and FormantFilter to reduce unwanted warnings
 
diff --git a/plugins/zynaddsubfx/src/DSP/Filter_.h b/plugins/zynaddsubfx/src/DSP/Filter_.h
index b577193f3..88716f0b2 100644
--- a/plugins/zynaddsubfx/src/DSP/Filter_.h
+++ b/plugins/zynaddsubfx/src/DSP/Filter_.h
@@ -33,7 +33,7 @@ class Filter_
         virtual void setfreq(REALTYPE frequency) = 0;
         virtual void setfreq_and_q(REALTYPE frequency, REALTYPE q_) = 0;
         virtual void setq(REALTYPE q_) = 0;
-        virtual void setgain(REALTYPE dBgain) {}
+        virtual void setgain(REALTYPE dBgain) = 0;
         REALTYPE outgain;
     private:
 };
diff --git a/plugins/zynaddsubfx/src/DSP/FormantFilter.cpp b/plugins/zynaddsubfx/src/DSP/FormantFilter.cpp
index 39c1002d9..529c210c2 100644
--- a/plugins/zynaddsubfx/src/DSP/FormantFilter.cpp
+++ b/plugins/zynaddsubfx/src/DSP/FormantFilter.cpp
@@ -191,6 +191,10 @@ void FormantFilter::setq(REALTYPE q_)
         formant[i]->setq(Qfactor * currentformants[i].q);
 }
 
+void FormantFilter::setgain(REALTYPE dBgain)
+{}
+
+
 void FormantFilter::setfreq_and_q(REALTYPE frequency, REALTYPE q_)
 {
     Qfactor = q_;
diff --git a/plugins/zynaddsubfx/src/DSP/FormantFilter.h b/plugins/zynaddsubfx/src/DSP/FormantFilter.h
index f62536123..4efe24fa5 100644
--- a/plugins/zynaddsubfx/src/DSP/FormantFilter.h
+++ b/plugins/zynaddsubfx/src/DSP/FormantFilter.h
@@ -38,6 +38,7 @@ class FormantFilter:public Filter_
         void setfreq(REALTYPE frequency);
         void setfreq_and_q(REALTYPE frequency, REALTYPE q_);
         void setq(REALTYPE q_);
+        void setgain(REALTYPE dBgain);
 
         void cleanup();
     private: