diff --git a/src/lib/time/formats.hpp b/src/lib/time/formats.hpp
index e374c407d..a5cccc321 100644
--- a/src/lib/time/formats.hpp
+++ b/src/lib/time/formats.hpp
@@ -178,7 +178,7 @@ namespace time {
         
         template<class F>
         size_t
-        typeID()
+        typeID()  const
           {
             return TypedContext<Supported>::ID<F>::get();
           }
@@ -210,7 +210,7 @@ namespace time {
         /** check if a specific Format is supported */
         template<class F>
         bool
-        check()
+        check()  const
           {
             return flags_[typeID<F>()];
           }
diff --git a/src/lib/time/quantiser.hpp b/src/lib/time/quantiser.hpp
index 20764bf33..c45489032 100644
--- a/src/lib/time/quantiser.hpp
+++ b/src/lib/time/quantiser.hpp
@@ -78,12 +78,20 @@ namespace time {
   class Quantiser
     : public Grid
     {
+    protected:
+      format::Supported supportedFormats_;
+      
+      Quantiser()
+        : supportedFormats_(format::SupportStandardTimecode())
+        { }
       
     public:
-      
       template<class FMT>
-      bool supports()  const;
-      
+      bool
+      supports()  const
+        {
+          return supportedFormats_.check<FMT>(); 
+        }
       
       
       //------Grid-API----------------------------------------------
@@ -116,11 +124,11 @@ namespace time {
       FixedFrameQuantiser (FrameRate const& frames_per_second, TimeValue referencePoint  =TimeValue(0));
       FixedFrameQuantiser (Duration const& frame_duration,     TimeValue referencePoint  =TimeValue(0));
       
-      
       long      gridPoint (TimeValue const&)  const;
       TimeValue gridAlign (TimeValue const&)  const;
       TimeValue timeOf    (long gridPoint)    const;
       TimeValue timeOf    (FSecs, int =0)     const;
+      
     };
   
   
diff --git a/src/lib/time/timequant.hpp b/src/lib/time/timequant.hpp
index 161d28bfb..3b25592c3 100644
--- a/src/lib/time/timequant.hpp
+++ b/src/lib/time/timequant.hpp
@@ -82,7 +82,7 @@ namespace time {
   inline bool
   QuTime::supports()  const
   {
-    return false;   ////////////////TODO;
+    return quantiser_->supports<FMT>();
   }
   
   
@@ -100,6 +100,7 @@ namespace time {
   QuTime::castInto (TC& timecode)  const
   {
     typedef typename TC::Format Format;
+    REQUIRE (supports<Format>());
     
     Format::rebuild (timecode, *quantiser_, TimeValue(*this));
   }