diff --git a/plug-ins/SpectralEditMulti.ny b/plug-ins/SpectralEditMulti.ny
index ef928c893..63b40a621 100644
--- a/plug-ins/SpectralEditMulti.ny
+++ b/plug-ins/SpectralEditMulti.ny
@@ -4,6 +4,9 @@
 ;name "Spectral edit multi tool"
 ;action "Calculating..."
 
+;control control-f0 "Low Frequency" real "" 4000 0 20000
+;control control-f1 "High Frequency" real "" 4000 0 20000
+
 (defun wet (sig)
   (cond
    ((not (or *f0* *f1*)) (throw 'error-message "Please select frequencies"))
diff --git a/plug-ins/SpectralEditParametricEQ.ny b/plug-ins/SpectralEditParametricEQ.ny
index 3a0faad0f..ff1a6bce3 100644
--- a/plug-ins/SpectralEditParametricEQ.ny
+++ b/plug-ins/SpectralEditParametricEQ.ny
@@ -5,7 +5,8 @@
 ;action "Calculating..."
 
 ;control control-gain "Gain (dB)" real "" 0 -24 24
-
+;control control-f0 "Low Frequency" real "" 4000 0 20000
+;control control-f1 "High Frequency" real "" 4000 0 20000
 
 (defun wet (sig gain)
   (cond
diff --git a/plug-ins/SpectralEditShelves.ny b/plug-ins/SpectralEditShelves.ny
index d6bbda5cc..ec855c429 100644
--- a/plug-ins/SpectralEditShelves.ny
+++ b/plug-ins/SpectralEditShelves.ny
@@ -5,6 +5,8 @@
 ;action "Calculating..."
 
 ;control control-gain "Gain (dB)" real "" 0 -24 24
+;control control-f0 "Low Frequency" real "" 4000 0 20000
+;control control-f1 "High Frequency" real "" 4000 0 20000
 
 (defun mid-shelf (sig lf hf gain)
   "Combines high shelf and low shelf filters"
diff --git a/src/effects/Effect.cpp b/src/effects/Effect.cpp
index d0a1fe40d..9b330e86e 100644
--- a/src/effects/Effect.cpp
+++ b/src/effects/Effect.cpp
@@ -107,6 +107,13 @@ bool Effect::DoEffect(wxWindow *parent, int flags,
 #ifdef EXPERIMENTAL_SPECTRAL_EDITING
    mF0 = selectedRegion->f0();
    mF1 = selectedRegion->f1();
+   wxArrayString Names;
+   if( mF0 != SelectedRegion::UndefinedFrequency )
+      Names.Add(wxT("control-f0"));
+   if( mF1 != SelectedRegion::UndefinedFrequency )
+      Names.Add(wxT("control-f1"));
+   SetPresetParameters( &Names, NULL );
+
 #endif
    CountWaveTracks();
 
diff --git a/src/effects/Effect.h b/src/effects/Effect.h
index 739f2db41..4684c034e 100644
--- a/src/effects/Effect.h
+++ b/src/effects/Effect.h
@@ -121,6 +121,11 @@ class AUDACITY_DLL_API Effect {
       return true;
    }
 
+   void SetPresetParameters( const wxArrayString * Names, const wxArrayString * Values ){
+      if( Names ) mPresetNames = *Names;
+      if( Values ) mPresetValues = *Values;
+   }
+
    void SetEffectFlags( int NewFlags )
    {
       mFlags = NewFlags;
@@ -221,6 +226,9 @@ class AUDACITY_DLL_API Effect {
    double         mF1;
 #endif
    TimeWarper     *mWarper;
+   wxArrayString  mPresetNames;
+   wxArrayString  mPresetValues;
+
 
  //
  // protected methods
diff --git a/src/effects/nyquist/Nyquist.cpp b/src/effects/nyquist/Nyquist.cpp
index 2874c7235..2f7436040 100644
--- a/src/effects/nyquist/Nyquist.cpp
+++ b/src/effects/nyquist/Nyquist.cpp
@@ -334,7 +334,10 @@ void EffectNyquist::Parse(wxString line)
 
       ctrl.val = UNINITIALIZED_CONTROL;
 
-      mControls.Add(ctrl);
+      if( mPresetNames.Index( ctrl.var ) == wxNOT_FOUND )
+      {
+         mControls.Add(ctrl);
+      }
    }
 
    if (len >= 2 && tokens[0] == wxT("categories")) {
@@ -580,7 +583,12 @@ bool EffectNyquist::PromptUser()
    }
 
    if (!mExternal) {
-      if (mFileName.GetModificationTime().IsLaterThan(mFileModified)) {
+      //TODO: re-instate the caching of the lisp parsing so it is only done once.
+      //small efficiency gain.
+      //Disabled for now in order to allow number of controls to be varied easily
+      //depending on whether time or time-and-frequency were selected.
+      //if (mFileName.GetModificationTime().IsLaterThan(mFileModified)) 
+      {
          ParseFile();
          mFileModified = mFileName.GetModificationTime();
       }