diff --git a/libs/ardour/ardour/midi_model.h b/libs/ardour/ardour/midi_model.h
index fb71f69085..8f8fd5c2cf 100644
--- a/libs/ardour/ardour/midi_model.h
+++ b/libs/ardour/ardour/midi_model.h
@@ -265,8 +265,8 @@ public:
 
 	bool write_section_to(boost::shared_ptr<MidiSource>     source,
 	                      const Glib::Threads::Mutex::Lock& source_lock,
-	                      Evoral::Beats                     begin = Evoral::MinBeats,
-	                      Evoral::Beats                     end   = Evoral::MaxBeats,
+	                      Evoral::Beats                     begin = Evoral::Beats(),
+	                      Evoral::Beats                     end   = std::numeric_limits<Evoral::Beats>::max(),
 	                      bool                              offset_events = false);
 
 	// MidiModel doesn't use the normal AutomationList serialisation code
diff --git a/libs/ardour/ardour/midi_source.h b/libs/ardour/ardour/midi_source.h
index f8f1e429ac..f1d9473a13 100644
--- a/libs/ardour/ardour/midi_source.h
+++ b/libs/ardour/ardour/midi_source.h
@@ -62,8 +62,8 @@ class LIBARDOUR_API MidiSource : virtual public Source, public boost::enable_sha
 	 */
 	int write_to (const Lock&                   lock,
 	              boost::shared_ptr<MidiSource> newsrc,
-	              Evoral::Beats                 begin = Evoral::MinBeats,
-	              Evoral::Beats                 end   = Evoral::MaxBeats);
+	              Evoral::Beats                 begin = Evoral::Beats(),
+	              Evoral::Beats                 end   = std::numeric_limits<Evoral::Beats>::max());
 
 	/** Export the midi data in the given time range to another MidiSource
 	 * \param newsrc MidiSource to which data will be written. Should be a
diff --git a/libs/ardour/midi_source.cc b/libs/ardour/midi_source.cc
index ea0bd15b0c..9af3009a73 100644
--- a/libs/ardour/midi_source.cc
+++ b/libs/ardour/midi_source.cc
@@ -408,7 +408,7 @@ MidiSource::write_to (const Lock& lock, boost::shared_ptr<MidiSource> newsrc, Ev
 	newsrc->copy_automation_state_from (this);
 
 	if (_model) {
-		if (begin == Evoral::MinBeats && end == Evoral::MaxBeats) {
+		if (begin == Evoral::Beats() && end == std::numeric_limits<Evoral::Beats>::max()) {
 			_model->write_to (newsrc, newsrc_lock);
 		} else {
 			_model->write_section_to (newsrc, newsrc_lock, begin, end);
@@ -422,7 +422,7 @@ MidiSource::write_to (const Lock& lock, boost::shared_ptr<MidiSource> newsrc, Ev
 
 	/* force a reload of the model if the range is partial */
 
-	if (begin != Evoral::MinBeats || end != Evoral::MaxBeats) {
+	if (begin != Evoral::Beats() || end != std::numeric_limits<Evoral::Beats>::max()) {
 		newsrc->load_model (newsrc_lock, true);
 	} else {
 		newsrc->set_model (newsrc_lock, _model);
diff --git a/libs/ardour/session_state.cc b/libs/ardour/session_state.cc
index 28a0725da8..bc91049589 100644
--- a/libs/ardour/session_state.cc
+++ b/libs/ardour/session_state.cc
@@ -1254,7 +1254,7 @@ Session::state (bool full_state, snapshot_t snapshot_type)
 					if (!ms->model()) {
 						ms->load_model (lm);
 					}
-					if (ms->write_to (lm, newsrc, Evoral::MinBeats, Evoral::MaxBeats)) {
+					if (ms->write_to (lm, newsrc, Evoral::Beats(), std::numeric_limits<Evoral::Beats>::max())) {
 						error << string_compose (_("Session-Save: Failed to copy MIDI Source '%1' for snapshot"), ancestor_name) << endmsg;
 					} else {
 						if (snapshot_type == SnapshotKeep) {