MusicalTime => Beats.

43 files changed, 425 insertions, 384 deletions

diff --git a/libs/ardour/ardour/beats_frames_converter.h b/libs/ardour/ardour/beats_frames_converter.h
index ada09b1179..908dd1909e 100644
--- a/libs/ardour/ardour/beats_frames_converter.h
+++ b/libs/ardour/ardour/beats_frames_converter.h
@@ -37,15 +37,15 @@ class TempoMap;
  *  them to the opposite unit, taking tempo changes into account.
  */
 class LIBARDOUR_API BeatsFramesConverter
-	: public Evoral::TimeConverter<Evoral::MusicalTime,framepos_t> {
+	: public Evoral::TimeConverter<Evoral::Beats,framepos_t> {
 public:
 	BeatsFramesConverter (TempoMap& tempo_map, framepos_t origin)
-		: Evoral::TimeConverter<Evoral::MusicalTime, framepos_t> (origin)
+		: Evoral::TimeConverter<Evoral::Beats, framepos_t> (origin)
 		, _tempo_map(tempo_map)
 	{}
 
-	framepos_t          to (Evoral::MusicalTime beats) const;
-	Evoral::MusicalTime from (framepos_t frames) const;
+	framepos_t    to (Evoral::Beats beats) const;
+	Evoral::Beats from (framepos_t frames) const;
 
 private:
 	TempoMap& _tempo_map;
diff --git a/libs/ardour/ardour/legatize.h b/libs/ardour/ardour/legatize.h
index 4a170e1a1c..78b384e1c7 100644
--- a/libs/ardour/ardour/legatize.h
+++ b/libs/ardour/ardour/legatize.h
@@ -39,10 +39,10 @@ public:
 	Legatize(bool shrink_only);
 	~Legatize();
 
-	typedef Evoral::Sequence<Evoral::MusicalTime>::Notes Notes;
+	typedef Evoral::Sequence<Evoral::Beats>::Notes Notes;
 
 	Command* operator()(boost::shared_ptr<ARDOUR::MidiModel> model,
-	                    Evoral::MusicalTime                  position,
+	                    Evoral::Beats                        position,
 	                    std::vector<Notes>&                  seqs);
 
 	std::string name() const { return std::string ("legatize"); }
diff --git a/libs/ardour/ardour/midi_model.h b/libs/ardour/ardour/midi_model.h
index b86a7436bb..4214431280 100644
--- a/libs/ardour/ardour/midi_model.h
+++ b/libs/ardour/ardour/midi_model.h
@@ -52,9 +52,9 @@ class MidiSource;
  * Because of this MIDI controllers and automatable controllers/widgets/etc
  * are easily interchangeable.
  */
-class LIBARDOUR_API MidiModel : public AutomatableSequence<Evoral::MusicalTime> {
+class LIBARDOUR_API MidiModel : public AutomatableSequence<Evoral::Beats> {
 public:
-	typedef Evoral::MusicalTime TimeType;
+	typedef Evoral::Beats TimeType;
 
 	MidiModel (boost::shared_ptr<MidiSource>);
 
@@ -259,8 +259,8 @@ public:
 
 	bool write_section_to(boost::shared_ptr<MidiSource>     source,
 	                      const Glib::Threads::Mutex::Lock& source_lock,
-	                      Evoral::MusicalTime               begin = Evoral::MinMusicalTime,
-	                      Evoral::MusicalTime               end   = Evoral::MaxMusicalTime);
+	                      Evoral::Beats                     begin = Evoral::MinBeats,
+	                      Evoral::Beats                     end   = Evoral::MaxBeats);
 
 	// MidiModel doesn't use the normal AutomationList serialisation code
 	// since controller data is stored in the .mid
diff --git a/libs/ardour/ardour/midi_operator.h b/libs/ardour/ardour/midi_operator.h
index 36e87b714b..b79544ed61 100644
--- a/libs/ardour/ardour/midi_operator.h
+++ b/libs/ardour/ardour/midi_operator.h
@@ -38,8 +38,8 @@ class LIBARDOUR_API MidiOperator {
 	virtual ~MidiOperator() {}
 
 	virtual Command* operator() (boost::shared_ptr<ARDOUR::MidiModel>,
-	                             Evoral::MusicalTime,
-	                             std::vector<Evoral::Sequence<Evoral::MusicalTime>::Notes>&) = 0;
+	                             Evoral::Beats,
+	                             std::vector<Evoral::Sequence<Evoral::Beats>::Notes>&) = 0;
 	virtual std::string name() const = 0;
 };
 
diff --git a/libs/ardour/ardour/midi_playlist_source.h b/libs/ardour/ardour/midi_playlist_source.h
index f064553342..6633be3c9e 100644
--- a/libs/ardour/ardour/midi_playlist_source.h
+++ b/libs/ardour/ardour/midi_playlist_source.h
@@ -45,7 +45,7 @@ public:
 	XMLNode& get_state ();
 	int set_state (const XMLNode&, int version);
 
-	void append_event_beats(const Glib::Threads::Mutex::Lock& lock, const Evoral::Event<Evoral::MusicalTime>& ev);
+	void append_event_beats(const Glib::Threads::Mutex::Lock& lock, const Evoral::Event<Evoral::Beats>& ev);
 	void append_event_frames(const Glib::Threads::Mutex::Lock& lock, const Evoral::Event<framepos_t>& ev, framepos_t source_start);
 	void load_model(const Glib::Threads::Mutex::Lock& lock, bool force_reload=false);
 	void destroy_model(const Glib::Threads::Mutex::Lock& lock);
diff --git a/libs/ardour/ardour/midi_region.h b/libs/ardour/ardour/midi_region.h
index 2a4e3a6190..ece23b65f0 100644
--- a/libs/ardour/ardour/midi_region.h
+++ b/libs/ardour/ardour/midi_region.h
@@ -37,8 +37,8 @@ namespace ARDOUR {
 		   MidiModel used by the MidiRegion
 		*/
 		LIBARDOUR_API extern PBD::PropertyDescriptor<void*> midi_data;
-		LIBARDOUR_API extern PBD::PropertyDescriptor<Evoral::MusicalTime> start_beats;
-		LIBARDOUR_API extern PBD::PropertyDescriptor<Evoral::MusicalTime> length_beats;
+		LIBARDOUR_API extern PBD::PropertyDescriptor<Evoral::Beats> start_beats;
+		LIBARDOUR_API extern PBD::PropertyDescriptor<Evoral::Beats> length_beats;
 	}
 }
 
@@ -114,8 +114,8 @@ class LIBARDOUR_API MidiRegion : public Region
 
   private:
 	friend class RegionFactory;
-	PBD::Property<Evoral::MusicalTime> _start_beats;
-	PBD::Property<Evoral::MusicalTime> _length_beats;
+	PBD::Property<Evoral::Beats> _start_beats;
+	PBD::Property<Evoral::Beats> _length_beats;
 
 	MidiRegion (const SourceList&);
 	MidiRegion (boost::shared_ptr<const MidiRegion>);
diff --git a/libs/ardour/ardour/midi_source.h b/libs/ardour/ardour/midi_source.h
index 2b78230a00..8a0c13681d 100644
--- a/libs/ardour/ardour/midi_source.h
+++ b/libs/ardour/ardour/midi_source.h
@@ -43,7 +43,7 @@ template<typename T> class MidiRingBuffer;
 class LIBARDOUR_API MidiSource : virtual public Source, public boost::enable_shared_from_this<MidiSource>
 {
   public:
-	typedef Evoral::MusicalTime TimeType;
+	typedef Evoral::Beats TimeType;
 
 	MidiSource (Session& session, std::string name, Source::Flag flags = Source::Flag(0));
 	MidiSource (Session& session, const XMLNode&);
@@ -59,8 +59,8 @@ class LIBARDOUR_API MidiSource : virtual public Source, public boost::enable_sha
 	 */
 	int write_to (const Lock&                   lock,
 	              boost::shared_ptr<MidiSource> newsrc,
-	              Evoral::MusicalTime           begin = Evoral::MinMusicalTime,
-	              Evoral::MusicalTime           end   = Evoral::MaxMusicalTime);
+	              Evoral::Beats                 begin = Evoral::MinBeats,
+	              Evoral::Beats                 end   = Evoral::MaxBeats);
 
 	/** Read the data in a given time range from the MIDI source.
 	 * All time stamps in parameters are in audio frames (even if the source has tempo time).
@@ -93,8 +93,8 @@ class LIBARDOUR_API MidiSource : virtual public Source, public boost::enable_sha
 	 *
 	 * Caller must ensure that the event is later than the last written event.
 	 */
-	virtual void append_event_beats(const Lock&                               lock,
-	                                const Evoral::Event<Evoral::MusicalTime>& ev) = 0;
+	virtual void append_event_beats(const Lock&                         lock,
+	                                const Evoral::Event<Evoral::Beats>& ev) = 0;
 
 	/** Append a single event with a timestamp in frames.
 	 *
@@ -132,9 +132,9 @@ class LIBARDOUR_API MidiSource : virtual public Source, public boost::enable_sha
 	 * etc.
 	 */
 	virtual void mark_midi_streaming_write_completed (
-		const Lock&                                            lock,
-		Evoral::Sequence<Evoral::MusicalTime>::StuckNoteOption stuck_option,
-		Evoral::MusicalTime                                    when = Evoral::MusicalTime());
+		const Lock&                                      lock,
+		Evoral::Sequence<Evoral::Beats>::StuckNoteOption stuck_option,
+		Evoral::Beats                                    when = Evoral::Beats());
 
 	virtual void session_saved();
 
@@ -205,11 +205,11 @@ class LIBARDOUR_API MidiSource : virtual public Source, public boost::enable_sha
 	boost::shared_ptr<MidiModel> _model;
 	bool                         _writing;
 
-	mutable Evoral::Sequence<Evoral::MusicalTime>::const_iterator _model_iter;
-	mutable bool                                                  _model_iter_valid;
+	mutable Evoral::Sequence<Evoral::Beats>::const_iterator _model_iter;
+	mutable bool                                            _model_iter_valid;
 
-	mutable Evoral::MusicalTime _length_beats;
-	mutable framepos_t          _last_read_end;
+	mutable Evoral::Beats _length_beats;
+	mutable framepos_t    _last_read_end;
 
 	/** The total duration of the current capture. */
 	framepos_t _capture_length;
diff --git a/libs/ardour/ardour/midi_state_tracker.h b/libs/ardour/ardour/midi_state_tracker.h
index 98611bc722..6690931422 100644
--- a/libs/ardour/ardour/midi_state_tracker.h
+++ b/libs/ardour/ardour/midi_state_tracker.h
@@ -46,7 +46,7 @@ public:
 	void remove (uint8_t note, uint8_t chn);
 	void resolve_notes (MidiBuffer& buffer, framepos_t time);
 	void resolve_notes (Evoral::EventSink<framepos_t>& buffer, framepos_t time);
-	void resolve_notes (MidiSource& src, const Glib::Threads::Mutex::Lock& lock, Evoral::MusicalTime time);
+	void resolve_notes (MidiSource& src, const Glib::Threads::Mutex::Lock& lock, Evoral::Beats time);
 	void dump (std::ostream&);
 	void reset ();
 	bool empty() const { return _on == 0; }
diff --git a/libs/ardour/ardour/quantize.h b/libs/ardour/ardour/quantize.h
index 09ba5f2aa2..639736b174 100644
--- a/libs/ardour/ardour/quantize.h
+++ b/libs/ardour/ardour/quantize.h
@@ -35,8 +35,8 @@ public:
 	~Quantize ();
 
 	Command* operator() (boost::shared_ptr<ARDOUR::MidiModel>,
-	                     Evoral::MusicalTime position,
-	                     std::vector<Evoral::Sequence<Evoral::MusicalTime>::Notes>&);
+	                     Evoral::Beats position,
+	                     std::vector<Evoral::Sequence<Evoral::Beats>::Notes>&);
 	std::string name() const { return std::string ("quantize"); }
 
 private:
diff --git a/libs/ardour/ardour/smf_source.h b/libs/ardour/ardour/smf_source.h
index d93fdb8506..29c6403694 100644
--- a/libs/ardour/ardour/smf_source.h
+++ b/libs/ardour/ardour/smf_source.h
@@ -51,14 +51,14 @@ public:
 		return safe_midi_file_extension(path);
 	}
 
-	void append_event_beats (const Lock& lock, const Evoral::Event<Evoral::MusicalTime>& ev);
+	void append_event_beats (const Lock& lock, const Evoral::Event<Evoral::Beats>& ev);
 	void append_event_frames (const Lock& lock, const Evoral::Event<framepos_t>& ev, framepos_t source_start);
 
 	void mark_streaming_midi_write_started (const Lock& lock, NoteMode mode);
 	void mark_streaming_write_completed (const Lock& lock);
 	void mark_midi_streaming_write_completed (const Lock& lock,
-	                                          Evoral::Sequence<Evoral::MusicalTime>::StuckNoteOption,
-	                                          Evoral::MusicalTime when = Evoral::MusicalTime());
+	                                          Evoral::Sequence<Evoral::Beats>::StuckNoteOption,
+	                                          Evoral::Beats when = Evoral::Beats());
 
 	XMLNode& get_state ();
 	int set_state (const XMLNode&, int version);
@@ -77,7 +77,7 @@ public:
 
   private:
 	bool _open;
-	Evoral::MusicalTime _last_ev_time_beats;
+	Evoral::Beats       _last_ev_time_beats;
 	framepos_t          _last_ev_time_frames;
 	/** end time (start + duration) of last call to read_unlocked */
 	mutable framepos_t _smf_last_read_end;
diff --git a/libs/ardour/ardour/tempo.h b/libs/ardour/ardour/tempo.h
index 19fe5b0b12..f2d314651d 100644
--- a/libs/ardour/ardour/tempo.h
+++ b/libs/ardour/ardour/tempo.h
@@ -276,9 +276,9 @@ class LIBARDOUR_API TempoMap : public PBD::StatefulDestructible
 	*/
 
 	framepos_t framepos_plus_bbt (framepos_t pos, Timecode::BBT_Time b) const;
-	framepos_t framepos_plus_beats (framepos_t, Evoral::MusicalTime) const;
-	framepos_t framepos_minus_beats (framepos_t, Evoral::MusicalTime) const;
-	Evoral::MusicalTime framewalk_to_beats (framepos_t pos, framecnt_t distance) const;
+	framepos_t framepos_plus_beats (framepos_t, Evoral::Beats) const;
+	framepos_t framepos_minus_beats (framepos_t, Evoral::Beats) const;
+	Evoral::Beats framewalk_to_beats (framepos_t pos, framecnt_t distance) const;
 
 	static const Tempo& default_tempo() { return _default_tempo; }
 	static const Meter& default_meter() { return _default_meter; }
diff --git a/libs/ardour/ardour/transform.h b/libs/ardour/ardour/transform.h
index 08e4a43521..df77244a17 100644
--- a/libs/ardour/ardour/transform.h
+++ b/libs/ardour/ardour/transform.h
@@ -50,9 +50,9 @@ namespace ARDOUR {
  */
 class LIBARDOUR_API Transform : public MidiOperator {
 public:
-	typedef Evoral::Sequence<Evoral::MusicalTime>::NotePtr NotePtr;
-	typedef Evoral::Sequence<Evoral::MusicalTime>::Notes   Notes;
-	typedef ARDOUR::MidiModel::NoteDiffCommand::Property   Property;
+	typedef Evoral::Sequence<Evoral::Beats>::NotePtr     NotePtr;
+	typedef Evoral::Sequence<Evoral::Beats>::Notes       Notes;
+	typedef ARDOUR::MidiModel::NoteDiffCommand::Property Property;
 
 	/** Context while iterating over notes during transformation. */
 	struct Context {
@@ -132,7 +132,7 @@ public:
 	Transform(const Program& prog);
 
 	Command* operator()(boost::shared_ptr<ARDOUR::MidiModel> model,
-	                    Evoral::MusicalTime                  position,
+	                    Evoral::Beats                        position,
 	                    std::vector<Notes>&                  seqs);
 
 	std::string name() const { return std::string ("transform"); }
diff --git a/libs/ardour/ardour/variant.h b/libs/ardour/ardour/variant.h
index 0402ffaa0b..9ecadbfe6a 100644
--- a/libs/ardour/ardour/variant.h
+++ b/libs/ardour/ardour/variant.h
@@ -57,7 +57,7 @@ public:
 	explicit Variant(int32_t value) : _type(INT)     { _int    = value; }
 	explicit Variant(int64_t value) : _type(LONG)    { _long   = value; }
 
-	explicit Variant(const Evoral::MusicalTime& beats)
+	explicit Variant(const Evoral::Beats& beats)
 		: _type(BEATS)
 		, _beats(beats)
 	{}
@@ -94,7 +94,7 @@ public:
 			                                std::min(value, (double)INT64_MAX)));
 			break;
 		case BEATS:
-			_beats = Evoral::MusicalTime(value);
+			_beats = Evoral::Beats(value);
 			break;
 		default:
 			_type = NOTHING;
@@ -158,19 +158,19 @@ public:
 		return false;
 	}
 
-	bool operator==(const Evoral::MusicalTime& v) const {
+	bool operator==(const Evoral::Beats& v) const {
 		return _type == BEATS && _beats == v;
 	}
 
 	bool operator!() const { return _type == NOTHING; }
 
-	Variant& operator=(Evoral::MusicalTime v) {
+	Variant& operator=(Evoral::Beats v) {
 		_type  = BEATS;
 		_beats = v;
 		return *this;
 	}
 
-	const Evoral::MusicalTime& get_beats() const {
+	const Evoral::Beats& get_beats() const {
 		ensure_type(BEATS); return _beats;
 	}
 
@@ -202,9 +202,9 @@ private:
 		}
 	}
 
-	Type                _type;    ///< Type tag
-	std::string         _string;  ///< PATH, STRING, URI
-	Evoral::MusicalTime _beats;   ///< BEATS
+	Type          _type;    ///< Type tag
+	std::string   _string;  ///< PATH, STRING, URI
+	Evoral::Beats _beats;   ///< BEATS
 
 	// Union of all primitive numeric types
 	union {
diff --git a/libs/ardour/beats_frames_converter.cc b/libs/ardour/beats_frames_converter.cc
index b99edbf51e..54db8008da 100644
--- a/libs/ardour/beats_frames_converter.cc
+++ b/libs/ardour/beats_frames_converter.cc
@@ -31,9 +31,9 @@ namespace ARDOUR {
  *  taking tempo changes into account.
  */
 framepos_t
-BeatsFramesConverter::to (Evoral::MusicalTime beats) const
+BeatsFramesConverter::to (Evoral::Beats beats) const
 {
-	if (beats < Evoral::MusicalTime()) {
+	if (beats < Evoral::Beats()) {
 		std::cerr << "negative beats passed to BFC: " << beats << std::endl;
 		PBD::stacktrace (std::cerr, 30);
 		return 0;
@@ -45,7 +45,7 @@ BeatsFramesConverter::to (Evoral::MusicalTime beats) const
  *  supplied to the constructor.  Returns the equivalent number of beats,
  *  taking tempo changes into account.
  */
-Evoral::MusicalTime
+Evoral::Beats
 BeatsFramesConverter::from (framepos_t frames) const
 {
 	return _tempo_map.framewalk_to_beats (_origin_b, frames);
@@ -60,7 +60,7 @@ DoubleBeatsFramesConverter::to (double beats) const
 		PBD::stacktrace (std::cerr, 30);
 		return 0;
 	}
-	return _tempo_map.framepos_plus_beats (_origin_b, Evoral::MusicalTime(beats)) - _origin_b;
+	return _tempo_map.framepos_plus_beats (_origin_b, Evoral::Beats(beats)) - _origin_b;
 }
 
 /** As above, but with beats in double instead (for GUI). */
diff --git a/libs/ardour/import.cc b/libs/ardour/import.cc
index eb2ed769d1..3ed028ef91 100644
--- a/libs/ardour/import.cc
+++ b/libs/ardour/import.cc
@@ -392,9 +392,9 @@ write_midi_data_to_new_files (Evoral::SMF* source, ImportStatus& status,
 
 				smfs->append_event_beats(
 					source_lock,
-					Evoral::Event<Evoral::MusicalTime>(
+					Evoral::Event<Evoral::Beats>(
 						0,
-						Evoral::MusicalTime::ticks_at_rate(t, source->ppqn()),
+						Evoral::Beats::ticks_at_rate(t, source->ppqn()),
 						size,
 						buf));
 
@@ -407,9 +407,9 @@ write_midi_data_to_new_files (Evoral::SMF* source, ImportStatus& status,
 
 				/* we wrote something */
 
-				const framepos_t          pos = 0;
-				const Evoral::MusicalTime length_beats = Evoral::MusicalTime::ticks_at_rate(t, source->ppqn());
-				BeatsFramesConverter      converter(smfs->session().tempo_map(), pos);
+				const framepos_t     pos          = 0;
+				const Evoral::Beats  length_beats = Evoral::Beats::ticks_at_rate(t, source->ppqn());
+				BeatsFramesConverter converter(smfs->session().tempo_map(), pos);
 				smfs->update_length(pos + converter.to(length_beats.round_up_to_beat()));
 				smfs->mark_streaming_write_completed (source_lock);
 
diff --git a/libs/ardour/legatize.cc b/libs/ardour/legatize.cc
index c5506fe6c0..0c118a6a48 100644
--- a/libs/ardour/legatize.cc
+++ b/libs/ardour/legatize.cc
@@ -31,7 +31,7 @@ Legatize::~Legatize ()
 
 Command*
 Legatize::operator()(boost::shared_ptr<ARDOUR::MidiModel> model,
-                     Evoral::MusicalTime                  position,
+                     Evoral::Beats                        position,
                      std::vector<Legatize::Notes>&        seqs)
 {
 	MidiModel::NoteDiffCommand* cmd = new MidiModel::NoteDiffCommand(model, "legatize");
@@ -43,10 +43,10 @@ Legatize::operator()(boost::shared_ptr<ARDOUR::MidiModel> model,
 				break;
 			}
 
-			const Evoral::MusicalTime new_end = (*next)->time() - Evoral::MusicalTime::tick();
+			const Evoral::Beats new_end = (*next)->time() - Evoral::Beats::tick();
 			if ((*i)->end_time() > new_end ||
 			    (!_shrink_only && (*i)->end_time() < new_end)) {
-				const Evoral::MusicalTime new_length(new_end - (*i)->time());
+				const Evoral::Beats new_length(new_end - (*i)->time());
 				cmd->change((*i), MidiModel::NoteDiffCommand::Length, new_length);
 			}
 
diff --git a/libs/ardour/midi_diskstream.cc b/libs/ardour/midi_diskstream.cc
index e52a7c3ad7..fed0dbc0ce 100644
--- a/libs/ardour/midi_diskstream.cc
+++ b/libs/ardour/midi_diskstream.cc
@@ -940,14 +940,14 @@ MidiDiskstream::transport_stopped_wallclock (struct tm& /*when*/, time_t /*twhen
 			/* set length in beats to entire capture length */
 
 			BeatsFramesConverter converter (_session.tempo_map(), capture_info.front()->start);
-			const Evoral::MusicalTime total_capture_beats = converter.from (total_capture);
+			const Evoral::Beats total_capture_beats = converter.from (total_capture);
 			_write_source->set_length_beats (total_capture_beats);
 
 			/* flush to disk: this step differs from the audio path,
 			   where all the data is already on disk.
 			*/
 
-			_write_source->mark_midi_streaming_write_completed (source_lock, Evoral::Sequence<Evoral::MusicalTime>::ResolveStuckNotes, total_capture_beats);
+			_write_source->mark_midi_streaming_write_completed (source_lock, Evoral::Sequence<Evoral::Beats>::ResolveStuckNotes, total_capture_beats);
 
 			/* we will want to be able to keep (over)writing the source
 			   but we don't want it to be removable. this also differs
diff --git a/libs/ardour/midi_model.cc b/libs/ardour/midi_model.cc
index 18378f5386..e3226e036f 100644
--- a/libs/ardour/midi_model.cc
+++ b/libs/ardour/midi_model.cc
@@ -620,7 +620,7 @@ MidiModel::NoteDiffCommand::unmarshal_change (XMLNode *xml_change)
 	if ((prop = xml_change->property ("old")) != 0) {
 		istringstream old_str (prop->value());
 		if (change.property == StartTime || change.property == Length) {
-			Evoral::MusicalTime old_time;
+			Evoral::Beats old_time;
 			old_str >> old_time;
 			change.old_value = old_time;
 		} else {
@@ -636,7 +636,7 @@ MidiModel::NoteDiffCommand::unmarshal_change (XMLNode *xml_change)
 	if ((prop = xml_change->property ("new")) != 0) {
 		istringstream new_str (prop->value());
 		if (change.property == StartTime || change.property == Length) {
-			Evoral::MusicalTime new_time;
+			Evoral::Beats new_time;
 			new_str >> new_time;
 			change.new_value = Variant(new_time);
 		} else {
@@ -1237,7 +1237,7 @@ MidiModel::PatchChangeDiffCommand::unmarshal_patch_change (XMLNode* n)
 {
 	XMLProperty* prop;
 	Evoral::event_id_t id = 0;
-	Evoral::MusicalTime time = Evoral::MusicalTime();
+	Evoral::Beats time = Evoral::Beats();
 	int channel = 0;
 	int program = 0;
 	int bank = 0;
@@ -1476,8 +1476,8 @@ MidiModel::sync_to_source (const Glib::Threads::Mutex::Lock& source_lock)
 bool
 MidiModel::write_section_to (boost::shared_ptr<MidiSource>     source,
                              const Glib::Threads::Mutex::Lock& source_lock,
-                             Evoral::MusicalTime               begin_time,
-                             Evoral::MusicalTime               end_time)
+                             Evoral::Beats                     begin_time,
+                             Evoral::Beats                     end_time)
 {
 	ReadLock lock(read_lock());
 	MidiStateTracker mst;
@@ -1489,12 +1489,12 @@ MidiModel::write_section_to (boost::shared_ptr<MidiSource>     source,
 	source->mark_streaming_midi_write_started (source_lock, note_mode());
 
 	for (Evoral::Sequence<TimeType>::const_iterator i = begin(TimeType(), true); i != end(); ++i) {
-		const Evoral::Event<Evoral::MusicalTime>& ev (*i);
+		const Evoral::Event<Evoral::Beats>& ev (*i);
 
 		if (ev.time() >= begin_time && ev.time() < end_time) {
 
-			const Evoral::MIDIEvent<Evoral::MusicalTime>* mev =
-				static_cast<const Evoral::MIDIEvent<Evoral::MusicalTime>* > (&ev);
+			const Evoral::MIDIEvent<Evoral::Beats>* mev =
+				static_cast<const Evoral::MIDIEvent<Evoral::Beats>* > (&ev);
 
 			if (!mev) {
 				continue;
@@ -2026,7 +2026,7 @@ MidiModel::transpose (TimeType from, TimeType to, int semitones)
 void
 MidiModel::control_list_marked_dirty ()
 {
-	AutomatableSequence<Evoral::MusicalTime>::control_list_marked_dirty ();
+	AutomatableSequence<Evoral::Beats>::control_list_marked_dirty ();
 	
 	ContentsChanged (); /* EMIT SIGNAL */
 }
diff --git a/libs/ardour/midi_playlist_source.cc b/libs/ardour/midi_playlist_source.cc
index 587bc7b12f..4f474f7119 100644
--- a/libs/ardour/midi_playlist_source.cc
+++ b/libs/ardour/midi_playlist_source.cc
@@ -149,7 +149,7 @@ MidiPlaylistSource::write_unlocked (const Lock&,
 }
 
 void
-MidiPlaylistSource::append_event_beats(const Glib::Threads::Mutex::Lock& /*lock*/, const Evoral::Event<Evoral::MusicalTime>& /*ev*/)
+MidiPlaylistSource::append_event_beats(const Glib::Threads::Mutex::Lock& /*lock*/, const Evoral::Event<Evoral::Beats>& /*ev*/)
 {
 	fatal << string_compose (_("programming error: %1"), "MidiPlaylistSource::append_event_beats() called - should be impossible") << endmsg;
 	abort(); /*NOTREACHED*/
diff --git a/libs/ardour/midi_region.cc b/libs/ardour/midi_region.cc
index 62c642d57b..c02caff470 100644
--- a/libs/ardour/midi_region.cc
+++ b/libs/ardour/midi_region.cc
@@ -53,9 +53,9 @@ using namespace PBD;
 
 namespace ARDOUR {
 	namespace Properties {
-		PBD::PropertyDescriptor<void*>                midi_data;
-		PBD::PropertyDescriptor<Evoral::MusicalTime>  start_beats;
-		PBD::PropertyDescriptor<Evoral::MusicalTime>  length_beats;
+		PBD::PropertyDescriptor<void*>         midi_data;
+		PBD::PropertyDescriptor<Evoral::Beats> start_beats;
+		PBD::PropertyDescriptor<Evoral::Beats> length_beats;
 	}
 }
 
@@ -80,7 +80,7 @@ MidiRegion::register_properties ()
 /* Basic MidiRegion constructor (many channels) */
 MidiRegion::MidiRegion (const SourceList& srcs)
 	: Region (srcs)
-	, _start_beats (Properties::start_beats, Evoral::MusicalTime())
+	, _start_beats (Properties::start_beats, Evoral::Beats())
 	, _length_beats (Properties::length_beats, midi_source(0)->length_beats())
 {
 	register_properties ();
@@ -94,7 +94,7 @@ MidiRegion::MidiRegion (const SourceList& srcs)
 MidiRegion::MidiRegion (boost::shared_ptr<const MidiRegion> other)
 	: Region (other)
 	, _start_beats (Properties::start_beats, other->_start_beats)
-	, _length_beats (Properties::length_beats, Evoral::MusicalTime())
+	, _length_beats (Properties::length_beats, Evoral::Beats())
 {
 	update_length_beats ();
 	register_properties ();
@@ -107,11 +107,11 @@ MidiRegion::MidiRegion (boost::shared_ptr<const MidiRegion> other)
 /** Create a new MidiRegion that is part of an existing one */
 MidiRegion::MidiRegion (boost::shared_ptr<const MidiRegion> other, frameoffset_t offset)
 	: Region (other, offset)
-	, _start_beats (Properties::start_beats, Evoral::MusicalTime())
-	, _length_beats (Properties::length_beats, Evoral::MusicalTime())
+	, _start_beats (Properties::start_beats, Evoral::Beats())
+	, _length_beats (Properties::length_beats, Evoral::Beats())
 {
 	BeatsFramesConverter bfc (_session.tempo_map(), _position);
-	Evoral::MusicalTime const offset_beats = bfc.from (offset);
+	Evoral::Beats const offset_beats = bfc.from (offset);
 
 	_start_beats  = other->_start_beats.val() + offset_beats;
 	_length_beats = other->_length_beats.val() - offset_beats;
@@ -147,8 +147,8 @@ boost::shared_ptr<MidiRegion>
 MidiRegion::clone (boost::shared_ptr<MidiSource> newsrc) const
 {
 	BeatsFramesConverter bfc (_session.tempo_map(), _position);
-	Evoral::MusicalTime const bbegin = bfc.from (_start);
-	Evoral::MusicalTime const bend = bfc.from (_start + _length);
+	Evoral::Beats const bbegin = bfc.from (_start);
+	Evoral::Beats const bend = bfc.from (_start + _length);
 
 	{
 		/* Lock our source since we'll be reading from it.  write_to() will
@@ -223,7 +223,7 @@ MidiRegion::set_position_internal (framepos_t pos, bool allow_bbt_recompute)
 	/* zero length regions don't exist - so if _length_beats is zero, this object
 	   is under construction.
 	*/
-	if (_length_beats.val() == Evoral::MusicalTime()) {
+	if (_length_beats.val() == Evoral::Beats()) {
 		/* leave _length_beats alone, and change _length to reflect the state of things
 		   at the new position (tempo map may dictate a different number of frames
 		*/
@@ -462,7 +462,7 @@ MidiRegion::fix_negative_start ()
 
 	model()->insert_silence_at_start (c.from (-_start));
 	_start = 0;
-	_start_beats = Evoral::MusicalTime();
+	_start_beats = Evoral::Beats();
 }
 
 /** Transpose the notes in this region by a given number of semitones */
diff --git a/libs/ardour/midi_source.cc b/libs/ardour/midi_source.cc
index 0c08adf4a5..8d3b130594 100644
--- a/libs/ardour/midi_source.cc
+++ b/libs/ardour/midi_source.cc
@@ -200,7 +200,7 @@ MidiSource::midi_read (const Lock&                        lm,
 
 	if (_model) {
 		// Find appropriate model iterator
-		Evoral::Sequence<Evoral::MusicalTime>::const_iterator& i = _model_iter;
+		Evoral::Sequence<Evoral::Beats>::const_iterator& i = _model_iter;
 		if (_last_read_end == 0 || start != _last_read_end || !_model_iter_valid) {
 			// Cached iterator is invalid, search for the first event past start
 			i                 = _model->begin(converter.from(start), false, filtered);
@@ -297,9 +297,9 @@ MidiSource::mark_streaming_write_started (const Lock& lock)
 }
 
 void
-MidiSource::mark_midi_streaming_write_completed (const Lock&                                            lock,
-                                                 Evoral::Sequence<Evoral::MusicalTime>::StuckNoteOption option,
-                                                 Evoral::MusicalTime                                    end)
+MidiSource::mark_midi_streaming_write_completed (const Lock&                                      lock,
+                                                 Evoral::Sequence<Evoral::Beats>::StuckNoteOption option,
+                                                 Evoral::Beats                                    end)
 {
 	if (_model) {
 		_model->end_write (option, end);
@@ -320,11 +320,11 @@ MidiSource::mark_midi_streaming_write_completed (const Lock&
 void
 MidiSource::mark_streaming_write_completed (const Lock& lock)
 {
-	mark_midi_streaming_write_completed (lock, Evoral::Sequence<Evoral::MusicalTime>::DeleteStuckNotes);
+	mark_midi_streaming_write_completed (lock, Evoral::Sequence<Evoral::Beats>::DeleteStuckNotes);
 }
 
 int
-MidiSource::write_to (const Lock& lock, boost::shared_ptr<MidiSource> newsrc, Evoral::MusicalTime begin, Evoral::MusicalTime end)
+MidiSource::write_to (const Lock& lock, boost::shared_ptr<MidiSource> newsrc, Evoral::Beats begin, Evoral::Beats end)
 {
 	Lock newsrc_lock (newsrc->mutex ());
 
@@ -333,7 +333,7 @@ MidiSource::write_to (const Lock& lock, boost::shared_ptr<MidiSource> newsrc, Ev
 	newsrc->copy_automation_state_from (this);
 
 	if (_model) {
-		if (begin == Evoral::MinMusicalTime && end == Evoral::MaxMusicalTime) {
+		if (begin == Evoral::MinBeats && end == Evoral::MaxBeats) {
 			_model->write_to (newsrc, newsrc_lock);
 		} else {
 			_model->write_section_to (newsrc, newsrc_lock, begin, end);
@@ -347,7 +347,7 @@ 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::MinMusicalTime || end != Evoral::MaxMusicalTime) {
+	if (begin != Evoral::MinBeats || end != Evoral::MaxBeats) {
 		newsrc->load_model (newsrc_lock, true);
 	} else {
 		newsrc->set_model (newsrc_lock, _model);
diff --git a/libs/ardour/midi_state_tracker.cc b/libs/ardour/midi_state_tracker.cc
index f919a02f35..9e96c4954f 100644
--- a/libs/ardour/midi_state_tracker.cc
+++ b/libs/ardour/midi_state_tracker.cc
@@ -168,7 +168,7 @@ MidiStateTracker::resolve_notes (Evoral::EventSink<framepos_t> &dst, framepos_t
 }
 
 void
-MidiStateTracker::resolve_notes (MidiSource& src, const MidiSource::Lock& lock, Evoral::MusicalTime time)
+MidiStateTracker::resolve_notes (MidiSource& src, const MidiSource::Lock& lock, Evoral::Beats time)
 {
 	DEBUG_TRACE (PBD::DEBUG::MidiTrackers, string_compose ("%1 MS-resolve notes @ %2 on = %3\n", this, time, _on));
 
@@ -181,7 +181,7 @@ MidiStateTracker::resolve_notes (MidiSource& src, const MidiSource::Lock& lock,
 	for (int channel = 0; channel < 16; ++channel) {
 		for (int note = 0; note < 128; ++note) {
 			while (_active_notes[note + 128 * channel]) {
-				Evoral::MIDIEvent<Evoral::MusicalTime> ev ((MIDI_CMD_NOTE_OFF|channel), time, 3, 0, true);
+				Evoral::MIDIEvent<Evoral::Beats> ev ((MIDI_CMD_NOTE_OFF|channel), time, 3, 0, true);
 				ev.set_type (MIDI_CMD_NOTE_OFF);
 				ev.set_channel (channel);
 				ev.set_note (note);
@@ -191,7 +191,7 @@ MidiStateTracker::resolve_notes (MidiSource& src, const MidiSource::Lock& lock,
 										       this, (int) note, (int) channel, time));
 				_active_notes[note + 128 * channel]--;
 				/* don't stack events up at the same time */
-				time += Evoral::MusicalTime::tick();
+				time += Evoral::Beats::tick();
 			}
 		}
 	}
diff --git a/libs/ardour/midi_stretch.cc b/libs/ardour/midi_stretch.cc
index 05635600d7..71ffcc21e1 100644
--- a/libs/ardour/midi_stretch.cc
+++ b/libs/ardour/midi_stretch.cc
@@ -108,7 +108,7 @@ MidiStretch::run (boost::shared_ptr<Region> r, Progress*)
 		new_model->append(ev, Evoral::next_event_id());
 	}
 
-	new_model->end_write (Evoral::Sequence<Evoral::MusicalTime>::DeleteStuckNotes);
+	new_model->end_write (Evoral::Sequence<Evoral::Beats>::DeleteStuckNotes);
 	new_model->set_edited (true);
 
 	new_src->copy_interpolation_from (src);
diff --git a/libs/ardour/quantize.cc b/libs/ardour/quantize.cc
index dc1976e9ff..6604469007 100644
--- a/libs/ardour/quantize.cc
+++ b/libs/ardour/quantize.cc
@@ -54,8 +54,8 @@ Quantize::~Quantize ()
 
 Command*
 Quantize::operator () (boost::shared_ptr<MidiModel> model,
-                       Evoral::MusicalTime position,
-                       std::vector<Evoral::Sequence<Evoral::MusicalTime>::Notes>& seqs)
+                       Evoral::Beats position,
+                       std::vector<Evoral::Sequence<Evoral::Beats>::Notes>& seqs)
 {
 	/* TODO: Rewrite this to be precise with fixed point? */
 
@@ -69,7 +69,7 @@ Quantize::operator () (boost::shared_ptr<MidiModel> model,
 	bool even;
 	MidiModel::NoteDiffCommand* cmd = new MidiModel::NoteDiffCommand (model, "quantize");
 
-	for (std::vector<Evoral::Sequence<Evoral::MusicalTime>::Notes>::iterator s = seqs.begin(); s != seqs.end(); ++s) {
+	for (std::vector<Evoral::Sequence<Evoral::Beats>::Notes>::iterator s = seqs.begin(); s != seqs.end(); ++s) {
 
 		even = false;
 
@@ -119,10 +119,10 @@ Quantize::operator () (boost::shared_ptr<MidiModel> model,
 				delta = new_end - (*i)->end_time().to_double();
 
 				if (fabs (delta) >= _threshold) {
-					Evoral::MusicalTime new_dur(new_end - new_start);
+					Evoral::Beats new_dur(new_end - new_start);
 
 					if (!new_dur) {
-						new_dur = Evoral::MusicalTime(_end_grid);
+						new_dur = Evoral::Beats(_end_grid);
 					}
 
 					cmd->change ((*i), MidiModel::NoteDiffCommand::Length, new_dur);
diff --git a/libs/ardour/smf_source.cc b/libs/ardour/smf_source.cc
index d1a82eb685..7f5e8059c9 100644
--- a/libs/ardour/smf_source.cc
+++ b/libs/ardour/smf_source.cc
@@ -278,7 +278,7 @@ SMFSource::read_unlocked (const Lock&                    lock,
 		/* Note that we add on the source start time (in session frames) here so that ev_frame_time
 		   is in session frames.
 		*/
-		const framepos_t ev_frame_time = converter.to(Evoral::MusicalTime::ticks_at_rate(time, ppqn())) + source_start;
+		const framepos_t ev_frame_time = converter.to(Evoral::Beats::ticks_at_rate(time, ppqn())) + source_start;
 
 		if (ev_frame_time < start + duration) {
 			destination.write (ev_frame_time, ev_type, ev_size, ev_buffer);
@@ -380,8 +380,8 @@ SMFSource::write_unlocked (const Lock&                 lock,
 
 /** Append an event with a timestamp in beats */
 void
-SMFSource::append_event_beats (const Glib::Threads::Mutex::Lock&         lock,
-                               const Evoral::Event<Evoral::MusicalTime>& ev)
+SMFSource::append_event_beats (const Glib::Threads::Mutex::Lock&   lock,
+                               const Evoral::Event<Evoral::Beats>& ev)
 {
 	if (!_writing || ev.size() == 0)  {
 		return;
@@ -391,9 +391,9 @@ SMFSource::append_event_beats (const Glib::Threads::Mutex::Lock&         lock,
                name().c_str(), ev.id(), ev.time(), ev.size());
 	       for (size_t i = 0; i < ev.size(); ++i) printf("%X ", ev.buffer()[i]); printf("\n");*/
 
-	Evoral::MusicalTime time = ev.time();
+	Evoral::Beats time = ev.time();
 	if (time < _last_ev_time_beats) {
-		const Evoral::MusicalTime difference = _last_ev_time_beats - time;
+		const Evoral::Beats difference = _last_ev_time_beats - time;
 		if (difference.to_double() / (double)ppqn() < 1.0) {
 			/* Close enough.  This problem occurs because Sequence is not
 			   actually ordered due to fuzzy time comparison.  I'm pretty sure
@@ -423,8 +423,8 @@ SMFSource::append_event_beats (const Glib::Threads::Mutex::Lock&         lock,
 
 	_length_beats = max(_length_beats, time);
 
-	const Evoral::MusicalTime delta_time_beats = time - _last_ev_time_beats;
-	const uint32_t            delta_time_ticks = delta_time_beats.to_ticks(ppqn());
+	const Evoral::Beats delta_time_beats = time - _last_ev_time_beats;
+	const uint32_t      delta_time_ticks = delta_time_beats.to_ticks(ppqn());
 
 	Evoral::SMF::append_event_delta(delta_time_ticks, ev.size(), ev.buffer(), event_id);
 	_last_ev_time_beats = time;
@@ -452,9 +452,9 @@ SMFSource::append_event_frames (const Glib::Threads::Mutex::Lock& lock,
 		return;
 	}
 
-	BeatsFramesConverter      converter(_session.tempo_map(), position);
-	const Evoral::MusicalTime ev_time_beats = converter.from(ev.time());
-	Evoral::event_id_t        event_id;
+	BeatsFramesConverter converter(_session.tempo_map(), position);
+	const Evoral::Beats  ev_time_beats = converter.from(ev.time());
+	Evoral::event_id_t   event_id;
 
 	if (ev.id() < 0) {
 		event_id  = Evoral::next_event_id();
@@ -463,18 +463,18 @@ SMFSource::append_event_frames (const Glib::Threads::Mutex::Lock& lock,
 	}
 
 	if (_model) {
-		const Evoral::Event<Evoral::MusicalTime> beat_ev (ev.event_type(),
-		                                                  ev_time_beats,
-		                                                  ev.size(),
-		                                                  const_cast<uint8_t*>(ev.buffer()));
+		const Evoral::Event<Evoral::Beats> beat_ev (ev.event_type(),
+		                                            ev_time_beats,
+		                                            ev.size(),
+		                                            const_cast<uint8_t*>(ev.buffer()));
 		_model->append (beat_ev, event_id);
 	}
 
 	_length_beats = max(_length_beats, ev_time_beats);
 
-	const Evoral::MusicalTime last_time_beats  = converter.from (_last_ev_time_frames);
-	const Evoral::MusicalTime delta_time_beats = ev_time_beats - last_time_beats;
-	const uint32_t            delta_time_ticks = delta_time_beats.to_ticks(ppqn());
+	const Evoral::Beats last_time_beats  = converter.from (_last_ev_time_frames);
+	const Evoral::Beats delta_time_beats = ev_time_beats - last_time_beats;
+	const uint32_t      delta_time_ticks = delta_time_beats.to_ticks(ppqn());
 
 	Evoral::SMF::append_event_delta(delta_time_ticks, ev.size(), ev.buffer(), event_id);
 	_last_ev_time_frames = ev.time();
@@ -518,18 +518,18 @@ SMFSource::mark_streaming_midi_write_started (const Lock& lock, NoteMode mode)
 
 	MidiSource::mark_streaming_midi_write_started (lock, mode);
 	Evoral::SMF::begin_write ();
-	_last_ev_time_beats  = Evoral::MusicalTime();
+	_last_ev_time_beats  = Evoral::Beats();
 	_last_ev_time_frames = 0;
 }
 
 void
 SMFSource::mark_streaming_write_completed (const Lock& lock)
 {
-	mark_midi_streaming_write_completed (lock, Evoral::Sequence<Evoral::MusicalTime>::DeleteStuckNotes);
+	mark_midi_streaming_write_completed (lock, Evoral::Sequence<Evoral::Beats>::DeleteStuckNotes);
 }
 
 void
-SMFSource::mark_midi_streaming_write_completed (const Lock& lm, Evoral::Sequence<Evoral::MusicalTime>::StuckNoteOption stuck_notes_option, Evoral::MusicalTime when)
+SMFSource::mark_midi_streaming_write_completed (const Lock& lm, Evoral::Sequence<Evoral::Beats>::StuckNoteOption stuck_notes_option, Evoral::Beats when)
 {
 	MidiSource::mark_midi_streaming_write_completed (lm, stuck_notes_option, when);
 
@@ -587,8 +587,8 @@ SMFSource::safe_midi_file_extension (const string& file)
 }
 
 static bool compare_eventlist (
-	const std::pair< Evoral::Event<Evoral::MusicalTime>*, gint >& a,
-	const std::pair< Evoral::Event<Evoral::MusicalTime>*, gint >& b) {
+	const std::pair< Evoral::Event<Evoral::Beats>*, gint >& a,
+	const std::pair< Evoral::Event<Evoral::Beats>*, gint >& b) {
 	return ( a.first->time() < b.first->time() );
 }
 
@@ -619,7 +619,7 @@ SMFSource::load_model (const Glib::Threads::Mutex::Lock& lock, bool force_reload
 	Evoral::SMF::seek_to_start();
 
 	uint64_t time = 0; /* in SMF ticks */
-	Evoral::Event<Evoral::MusicalTime> ev;
+	Evoral::Event<Evoral::Beats> ev;
 
 	uint32_t scratch_size = 0; // keep track of scratch and minimize reallocs
 
@@ -631,7 +631,7 @@ SMFSource::load_model (const Glib::Threads::Mutex::Lock& lock, bool force_reload
 	bool have_event_id;
 
 	// TODO simplify event allocation
-	std::list< std::pair< Evoral::Event<Evoral::MusicalTime>*, gint > > eventlist;
+	std::list< std::pair< Evoral::Event<Evoral::Beats>*, gint > > eventlist;
 
 	for (unsigned i = 1; i <= num_tracks(); ++i) {
 		if (seek_to_track(i)) continue;
@@ -658,7 +658,7 @@ SMFSource::load_model (const Glib::Threads::Mutex::Lock& lock, bool force_reload
 					event_id = Evoral::next_event_id();
 				}
 				const uint32_t            event_type = midi_parameter_type(buf[0]);
-				const Evoral::MusicalTime event_time = Evoral::MusicalTime::ticks_at_rate(time, ppqn());
+				const Evoral::Beats event_time = Evoral::Beats::ticks_at_rate(time, ppqn());
 #ifndef NDEBUG
 				std::string ss;
 
@@ -673,7 +673,7 @@ SMFSource::load_model (const Glib::Threads::Mutex::Lock& lock, bool force_reload
 #endif
 
 				eventlist.push_back(make_pair (
-							new Evoral::Event<Evoral::MusicalTime> (
+							new Evoral::Event<Evoral::Beats> (
 								event_type, event_time,
 								size, buf, true)
 							, event_id));
@@ -692,13 +692,13 @@ SMFSource::load_model (const Glib::Threads::Mutex::Lock& lock, bool force_reload
 
 	eventlist.sort(compare_eventlist);
 
-	std::list< std::pair< Evoral::Event<Evoral::MusicalTime>*, gint > >::iterator it;
+	std::list< std::pair< Evoral::Event<Evoral::Beats>*, gint > >::iterator it;
 	for (it=eventlist.begin(); it!=eventlist.end(); ++it) {
 		_model->append (*it->first, it->second);
 		delete it->first;
 	}
 
-	_model->end_write (Evoral::Sequence<Evoral::MusicalTime>::ResolveStuckNotes, _length_beats);
+	_model->end_write (Evoral::Sequence<Evoral::Beats>::ResolveStuckNotes, _length_beats);
 	_model->set_edited (false);
 	invalidate(lock);
 
diff --git a/libs/ardour/tempo.cc b/libs/ardour/tempo.cc
index 486cbb0643..dfcc264547 100644
--- a/libs/ardour/tempo.cc
+++ b/libs/ardour/tempo.cc
@@ -1841,7 +1841,7 @@ TempoMap::insert_time (framepos_t where, framecnt_t amount)
  *  pos can be -ve, if required.
  */
 framepos_t
-TempoMap::framepos_plus_beats (framepos_t pos, Evoral::MusicalTime beats) const
+TempoMap::framepos_plus_beats (framepos_t pos, Evoral::Beats beats) const
 {
 	Glib::Threads::RWLock::ReaderLock lm (lock);
 	Metrics::const_iterator next_tempo;
@@ -1891,11 +1891,11 @@ TempoMap::framepos_plus_beats (framepos_t pos, Evoral::MusicalTime beats) const
 		framecnt_t distance_frames = (next_tempo == metrics.end() ? max_framepos : ((*next_tempo)->frame() - pos));
 
 		/* Distance to the end in beats */
-		Evoral::MusicalTime distance_beats = Evoral::MusicalTime::ticks_at_rate(
+		Evoral::Beats distance_beats = Evoral::Beats::ticks_at_rate(
 			distance_frames, tempo->frames_per_beat (_frame_rate));
 
 		/* Amount to subtract this time */
-		Evoral::MusicalTime const delta = min (distance_beats, beats);
+		Evoral::Beats const delta = min (distance_beats, beats);
 
 		DEBUG_TRACE (DEBUG::TempoMath, string_compose ("\tdistance to %1 = %2 (%3 beats)\n",
 							       (next_tempo == metrics.end() ? max_framepos : (*next_tempo)->frame()),
@@ -1933,7 +1933,7 @@ TempoMap::framepos_plus_beats (framepos_t pos, Evoral::MusicalTime beats) const
 
 /** Subtract some (fractional) beats from a frame position, and return the result in frames */
 framepos_t
-TempoMap::framepos_minus_beats (framepos_t pos, Evoral::MusicalTime beats) const
+TempoMap::framepos_minus_beats (framepos_t pos, Evoral::Beats beats) const
 {
 	Glib::Threads::RWLock::ReaderLock lm (lock);
 	Metrics::const_reverse_iterator prev_tempo;
@@ -2000,11 +2000,11 @@ TempoMap::framepos_minus_beats (framepos_t pos, Evoral::MusicalTime beats) const
 		framecnt_t distance_frames = (pos - tempo->frame());
 
 		/* Distance to the start in beats */
-		Evoral::MusicalTime distance_beats = Evoral::MusicalTime::ticks_at_rate(
+		Evoral::Beats distance_beats = Evoral::Beats::ticks_at_rate(
 			distance_frames, tempo->frames_per_beat (_frame_rate));
 
 		/* Amount to subtract this time */
-		Evoral::MusicalTime const sub = min (distance_beats, beats);
+		Evoral::Beats const sub = min (distance_beats, beats);
 
 		DEBUG_TRACE (DEBUG::TempoMath, string_compose ("\tdistance to %1 = %2 (%3 beats)\n",
 							       tempo->frame(), distance_frames, distance_beats));
@@ -2037,7 +2037,7 @@ TempoMap::framepos_minus_beats (framepos_t pos, Evoral::MusicalTime beats) const
 			}
 		} else {
 			pos -= llrint (beats.to_double() * tempo->frames_per_beat (_frame_rate));
-			beats = Evoral::MusicalTime();
+			beats = Evoral::Beats();
 		}
 	}
 
@@ -2183,7 +2183,7 @@ TempoMap::framepos_plus_bbt (framepos_t pos, BBT_Time op) const
 /** Count the number of beats that are equivalent to distance when going forward,
     starting at pos.
 */
-Evoral::MusicalTime
+Evoral::Beats
 TempoMap::framewalk_to_beats (framepos_t pos, framecnt_t distance) const
 {
 	Glib::Threads::RWLock::ReaderLock lm (lock);
@@ -2218,7 +2218,7 @@ TempoMap::framewalk_to_beats (framepos_t pos, framecnt_t distance) const
 	             string_compose ("frame %1 walk by %2 frames, start with tempo = %3 @ %4\n",
 	                             pos, distance, *((const Tempo*)tempo), tempo->frame()));
 	
-	Evoral::MusicalTime beats = Evoral::MusicalTime();
+	Evoral::Beats beats = Evoral::Beats();
 
 	while (distance) {
 
@@ -2246,7 +2246,7 @@ TempoMap::framewalk_to_beats (framepos_t pos, framecnt_t distance) const
 		pos += sub;
 		distance -= sub;
 		assert (tempo);
-		beats += Evoral::MusicalTime::ticks_at_rate(sub, tempo->frames_per_beat (_frame_rate));
+		beats += Evoral::Beats::ticks_at_rate(sub, tempo->frames_per_beat (_frame_rate));
 
 		DEBUG_TRACE (DEBUG::TempoMath, string_compose ("now at %1, beats = %2 distance left %3\n",
 							       pos, beats, distance));
diff --git a/libs/ardour/test/framepos_minus_beats_test.cc b/libs/ardour/test/framepos_minus_beats_test.cc
index e4c4844146..cc6341fb0b 100644
--- a/libs/ardour/test/framepos_minus_beats_test.cc
+++ b/libs/ardour/test/framepos_minus_beats_test.cc
@@ -26,11 +26,11 @@ FrameposMinusBeatsTest::singleTempoTest ()
 	map.add_tempo (tempo, BBT_Time (1, 1, 0));
 
 	/* Subtract 1 beat from beat 3 of the first bar */
-	framepos_t r = map.framepos_minus_beats (frames_per_beat * 2, MusicalTime(1));
+	framepos_t r = map.framepos_minus_beats (frames_per_beat * 2, Beats(1));
 	CPPUNIT_ASSERT_EQUAL (r, framepos_t (frames_per_beat * 1));
 
 	/* Subtract 4 beats from 3 beats in, to go beyond zero */
-	r = map.framepos_minus_beats (frames_per_beat * 3, MusicalTime(4));
+	r = map.framepos_minus_beats (frames_per_beat * 3, Beats(4));
 	CPPUNIT_ASSERT_EQUAL (r, framepos_t (- frames_per_beat));
 }
 
@@ -70,15 +70,15 @@ FrameposMinusBeatsTest::doubleTempoTest ()
 	/* Now some tests */
 
 	/* Subtract 1 beat from 1|2 */
-	framepos_t r = map.framepos_minus_beats (24e3, MusicalTime(1));
+	framepos_t r = map.framepos_minus_beats (24e3, Beats(1));
 	CPPUNIT_ASSERT_EQUAL (r, framepos_t (0));
 
 	/* Subtract 2 beats from 4|2 (over the tempo change) */
-	r = map.framepos_minus_beats (288e3 + 12e3, MusicalTime(2));
+	r = map.framepos_minus_beats (288e3 + 12e3, Beats(2));
 	CPPUNIT_ASSERT_EQUAL (r, framepos_t (288e3 - 24e3));
 
 	/* Subtract 2.5 beats from 4|2 (over the tempo change) */
-	r = map.framepos_minus_beats (288e3 + 12e3, MusicalTime(2.5));
+	r = map.framepos_minus_beats (288e3 + 12e3, Beats(2.5));
 	CPPUNIT_ASSERT_EQUAL (r, framepos_t (288e3 - 24e3 - 12e3));
 }
 
@@ -124,15 +124,15 @@ FrameposMinusBeatsTest::doubleTempoWithMeterTest ()
 	/* Now some tests */
 
 	/* Subtract 1 beat from 1|2 */
-	framepos_t r = map.framepos_minus_beats (24e3, MusicalTime(1));
+	framepos_t r = map.framepos_minus_beats (24e3, Beats(1));
 	CPPUNIT_ASSERT_EQUAL (r, framepos_t (0));
 
 	/* Subtract 2 beats from 4|2 (over the tempo change) */
-	r = map.framepos_minus_beats (288e3 + 12e3, MusicalTime(2));
+	r = map.framepos_minus_beats (288e3 + 12e3, Beats(2));
 	CPPUNIT_ASSERT_EQUAL (r, framepos_t (288e3 - 24e3));
 
 	/* Subtract 2.5 beats from 4|2 (over the tempo change) */
-	r = map.framepos_minus_beats (288e3 + 12e3, MusicalTime(2.5));
+	r = map.framepos_minus_beats (288e3 + 12e3, Beats(2.5));
 	CPPUNIT_ASSERT_EQUAL (r, framepos_t (288e3 - 24e3 - 12e3));
 }
 
diff --git a/libs/ardour/test/framepos_plus_beats_test.cc b/libs/ardour/test/framepos_plus_beats_test.cc
index abe1310f62..efc57c5872 100644
--- a/libs/ardour/test/framepos_plus_beats_test.cc
+++ b/libs/ardour/test/framepos_plus_beats_test.cc
@@ -25,11 +25,11 @@ FrameposPlusBeatsTest::singleTempoTest ()
 	map.add_tempo (tempo, BBT_Time (1, 1, 0));
 
 	/* Add 1 beat to beat 3 of the first bar */
-	framepos_t r = map.framepos_plus_beats (frames_per_beat * 2, Evoral::MusicalTime(1));
+	framepos_t r = map.framepos_plus_beats (frames_per_beat * 2, Evoral::Beats(1));
 	CPPUNIT_ASSERT_EQUAL (framepos_t (frames_per_beat * 3), r);
 
 	/* Add 4 beats to a -ve frame of 1 beat before zero */
-	r = map.framepos_plus_beats (-frames_per_beat * 1, Evoral::MusicalTime(4));
+	r = map.framepos_plus_beats (-frames_per_beat * 1, Evoral::Beats(4));
 	CPPUNIT_ASSERT_EQUAL (framepos_t (frames_per_beat * 3), r);
 }
 
@@ -69,15 +69,15 @@ FrameposPlusBeatsTest::doubleTempoTest ()
 	/* Now some tests */
 
 	/* Add 1 beat to 1|2 */
-	framepos_t r = map.framepos_plus_beats (24e3, Evoral::MusicalTime(1));
+	framepos_t r = map.framepos_plus_beats (24e3, Evoral::Beats(1));
 	CPPUNIT_ASSERT_EQUAL (framepos_t (48e3), r);
 
 	/* Add 2 beats to 3|4 (over the tempo change) */
-	r = map.framepos_plus_beats (264e3, Evoral::MusicalTime(2));
+	r = map.framepos_plus_beats (264e3, Evoral::Beats(2));
 	CPPUNIT_ASSERT_EQUAL (framepos_t (264e3 + 24e3 + 12e3), r);
 
 	/* Add 2.5 beats to 3|3|960 (over the tempo change) */
-	r = map.framepos_plus_beats (264e3 - 12e3, Evoral::MusicalTime(2.5));
+	r = map.framepos_plus_beats (264e3 - 12e3, Evoral::Beats(2.5));
 	CPPUNIT_ASSERT_EQUAL (framepos_t (264e3 + 24e3 + 12e3), r);
 }
 
@@ -123,15 +123,15 @@ FrameposPlusBeatsTest::doubleTempoWithMeterTest ()
 	/* Now some tests */
 
 	/* Add 1 beat to 1|2 */
-	framepos_t r = map.framepos_plus_beats (24e3, Evoral::MusicalTime(1));
+	framepos_t r = map.framepos_plus_beats (24e3, Evoral::Beats(1));
 	CPPUNIT_ASSERT_EQUAL (framepos_t (48e3), r);
 
 	/* Add 2 beats to 3|4 (over the tempo change) */
-	r = map.framepos_plus_beats (264e3, Evoral::MusicalTime(2));
+	r = map.framepos_plus_beats (264e3, Evoral::Beats(2));
 	CPPUNIT_ASSERT_EQUAL (framepos_t (264e3 + 24e3 + 12e3), r);
 
 	/* Add 2.5 beats to 3|3|960 (over the tempo change) */
-	r = map.framepos_plus_beats (264e3 - 12e3, Evoral::MusicalTime(2.5));
+	r = map.framepos_plus_beats (264e3 - 12e3, Evoral::Beats(2.5));
 	CPPUNIT_ASSERT_EQUAL (framepos_t (264e3 + 24e3 + 12e3), r);
 }
 
diff --git a/libs/ardour/transform.cc b/libs/ardour/transform.cc
index 3b4f53c860..9f029829de 100644
--- a/libs/ardour/transform.cc
+++ b/libs/ardour/transform.cc
@@ -121,7 +121,7 @@ Transform::Operation::eval(Context& ctx) const
 
 Command*
 Transform::operator()(boost::shared_ptr<MidiModel> model,
-                      Evoral::MusicalTime          position,
+                      Evoral::Beats                position,
                       std::vector<Notes>&          seqs)
 {
 	typedef MidiModel::NoteDiffCommand Command;
diff --git a/libs/evoral/evoral/Beats.hpp b/libs/evoral/evoral/Beats.hpp
new file mode 100644
index 0000000000..e0277c4b3d
--- /dev/null
+++ b/libs/evoral/evoral/Beats.hpp
@@ -0,0 +1,247 @@
+/* This file is part of Evoral.
+ * Copyright (C) 2008-2015 David Robillard <http://drobilla.net>
+ * Copyright (C) 2000-2008 Paul Davis
+ *
+ * Evoral is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License as published by the Free Software
+ * Foundation; either version 2 of the License, or (at your option) any later
+ * version.
+ *
+ * Evoral is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef EVORAL_BEATS_HPP
+#define EVORAL_BEATS_HPP
+
+#include <float.h>
+#include <math.h>
+#include <stdint.h>
+
+#include <iostream>
+#include <limits>
+
+#include "evoral/visibility.h"
+
+namespace Evoral {
+
+/** Musical time in beats. */
+class /*LIBEVORAL_API*/ Beats {
+public:
+	LIBEVORAL_API static const double PPQN;
+
+	Beats() : _time(0.0) {}
+
+	/** Create from a real number of beats. */
+	explicit Beats(double time) : _time(time) {}
+
+	/** Create from an integer number of beats. */
+	static Beats beats(int32_t beats) {
+		return Beats((double)beats);
+	}
+
+	/** Create from ticks at the standard PPQN. */
+	static Beats ticks(uint32_t ticks) {
+		return Beats(ticks / PPQN);
+	}
+
+	/** Create from ticks at a given rate.
+	 *
+	 * Note this can also be used to create from frames by setting ppqn to the
+	 * number of samples per beat.
+	 */
+	static Beats ticks_at_rate(uint64_t ticks, uint32_t ppqn) {
+		return Beats((double)ticks / (double)ppqn);
+	}
+
+	Beats& operator=(const Beats& other) {
+		_time = other._time;
+		return *this;
+	}
+
+	Beats round_up_to_beat() const {
+		return Evoral::Beats(ceil(_time));
+	}
+
+	Beats round_down_to_beat() const {
+		return Evoral::Beats(floor(_time));
+	}
+
+	Beats snap_to(const Evoral::Beats& snap) const {
+		return Beats(ceil(_time / snap._time) * snap._time);
+	}
+
+	inline bool operator==(const Beats& b) const {
+		/* Acceptable tolerance is 1 tick. */
+		return fabs(_time - b._time) <= (1.0 / PPQN);
+	}
+
+	inline bool operator==(double t) const {
+		/* Acceptable tolerance is 1 tick. */
+		return fabs(_time - t) <= (1.0 / PPQN);
+	}
+
+	inline bool operator==(int beats) const {
+		/* Acceptable tolerance is 1 tick. */
+		return fabs(_time - beats) <= (1.0 / PPQN);
+	}
+
+	inline bool operator!=(const Beats& b) const {
+		return !operator==(b);
+	}
+
+	inline bool operator<(const Beats& b) const {
+		/* Acceptable tolerance is 1 tick. */
+		if (fabs(_time - b._time) <= (1.0 / PPQN)) {
+			return false;  /* Effectively identical. */
+		} else {
+			return _time < b._time;
+		}
+	}
+
+	inline bool operator<=(const Beats& b) const {
+		return operator==(b) || operator<(b);
+	}
+
+	inline bool operator>(const Beats& b) const {
+		/* Acceptable tolerance is 1 tick. */
+		if (fabs(_time - b._time) <= (1.0 / PPQN)) {
+			return false;  /* Effectively identical. */
+		} else {
+			return _time > b._time;
+		}
+	}
+
+	inline bool operator>=(const Beats& b) const {
+		return operator==(b) || operator>(b);
+	}
+
+	inline bool operator<(double b) const {
+		/* Acceptable tolerance is 1 tick. */
+		if (fabs(_time - b) <= (1.0 / PPQN)) {
+			return false;  /* Effectively identical. */
+		} else {
+			return _time < b;
+		}
+	}
+
+	inline bool operator<=(double b) const {
+		return operator==(b) || operator<(b);
+	}
+
+	inline bool operator>(double b) const {
+		/* Acceptable tolerance is 1 tick. */
+		if (fabs(_time - b) <= (1.0 / PPQN)) {
+			return false;  /* Effectively identical. */
+		} else {
+			return _time > b;
+		}
+	}
+
+	inline bool operator>=(double b) const {
+		return operator==(b) || operator>(b);
+	}
+
+	Beats operator+(const Beats& b) const {
+		return Beats(_time + b._time);
+	}
+
+	Beats operator-(const Beats& b) const {
+		return Beats(_time - b._time);
+	}
+
+	Beats operator+(double d) const {
+		return Beats(_time + d);
+	}
+
+	Beats operator-(double d) const {
+		return Beats(_time - d);
+	}
+
+	Beats operator-() const {
+		return Beats(-_time);
+	}
+
+	template<typename Number>
+	Beats operator*(Number factor) const {
+		return Beats(_time * factor);
+	}
+
+	Beats& operator+=(const Beats& b) {
+		_time += b._time;
+		return *this;
+	}
+
+	Beats& operator-=(const Beats& b) {
+		_time -= b._time;
+		return *this;
+	}
+
+	double   to_double()              const { return _time; }
+	uint64_t to_ticks()               const { return lrint(_time * PPQN); }
+	uint64_t to_ticks(uint32_t ppqn)  const { return lrint(_time * ppqn); }
+
+	uint32_t get_beats() const { return floor(_time); }
+	uint32_t get_ticks() const { return (uint32_t)lrint(fmod(_time, 1.0) * PPQN); }
+
+	bool operator!() const { return _time == 0; }
+
+	static Beats min()  { return Beats(DBL_MIN); }
+	static Beats max()  { return Beats(DBL_MAX); }
+	static Beats tick() { return Beats(1.0 / PPQN); }
+
+private:
+	double _time;
+};
+
+extern LIBEVORAL_API const Beats MaxBeats;
+extern LIBEVORAL_API const Beats MinBeats;
+
+/*
+  TIL, several horrible hours later, that sometimes the compiler looks in the
+  namespace of a type (Evoral::Beats in this case) for an operator, and
+  does *NOT* look in the global namespace.
+
+  C++ is proof that hell exists and we are living in it.  In any case, move
+  these to the global namespace and PBD::Property's loopy
+  virtual-method-in-a-template will bite you.
+*/
+
+inline std::ostream&
+operator<<(std::ostream& os, const Beats& t)
+{
+	os << t.to_double();
+	return os;
+}
+
+inline std::istream&
+operator>>(std::istream& is, Beats& t)
+{
+	double beats;
+	is >> beats;
+	t = Beats(beats);
+	return is;
+}
+
+} // namespace Evoral
+
+namespace PBD {
+	namespace DEBUG {
+		LIBEVORAL_API extern uint64_t Beats;
+	}
+}
+
+namespace std {
+	template<>
+	struct numeric_limits<Evoral::Beats> {
+		static Evoral::Beats min() { return Evoral::Beats::min(); }
+		static Evoral::Beats max() { return Evoral::Beats::max(); }
+	};
+}
+
+#endif // EVORAL_BEATS_HPP
diff --git a/libs/evoral/evoral/types.hpp b/libs/evoral/evoral/types.hpp
index 14ba36acdf..1951fb8ba6 100644
--- a/libs/evoral/evoral/types.hpp
+++ b/libs/evoral/evoral/types.hpp
@@ -27,6 +27,7 @@
 #include <limits>
 #include <list>
 
+#include "evoral/Beats.hpp"
 #include "evoral/visibility.h"
 
 #include "pbd/debug.h"
@@ -38,207 +39,9 @@ namespace Evoral {
 */
 typedef int32_t event_id_t;
 
-/** Musical time: beats relative to some defined origin */
-class /*LIBEVORAL_API*/ MusicalTime {
-public:
-	LIBEVORAL_API static const double PPQN;
-
-	MusicalTime() : _time(0.0) {}
-
-	/** Create from a real number of beats. */
-	explicit MusicalTime(double time) : _time(time) {}
-
-	/** Create from an integer number of beats. */
-	static MusicalTime beats(int32_t beats) {
-		return MusicalTime((double)beats);
-	}
-
-	/** Create from ticks at the standard PPQN. */
-	static MusicalTime ticks(uint32_t ticks) {
-		return MusicalTime(ticks / PPQN);
-	}
-
-	/** Create from ticks at a given rate.
-	 *
-	 * Note this can also be used to create from frames by setting ppqn to the
-	 * number of samples per beat.
-	 */
-	static MusicalTime ticks_at_rate(uint64_t ticks, uint32_t ppqn) {
-		return MusicalTime((double)ticks / (double)ppqn);
-	}
-
-	MusicalTime& operator=(const MusicalTime& other) {
-		_time = other._time;
-		return *this;
-	}
-
-	MusicalTime round_up_to_beat() const {
-		return Evoral::MusicalTime(ceil(_time));
-	}
-
-	MusicalTime round_down_to_beat() const {
-		return Evoral::MusicalTime(floor(_time));
-	}
-
-	MusicalTime snap_to(const Evoral::MusicalTime& snap) const {
-		return MusicalTime(ceil(_time / snap._time) * snap._time);
-	}
-
-	inline bool operator==(const MusicalTime& b) const {
-		/* Acceptable tolerance is 1 tick. */
-		return fabs(_time - b._time) <= (1.0 / PPQN);
-	}
-
-	inline bool operator==(double t) const {
-		/* Acceptable tolerance is 1 tick. */
-		return fabs(_time - t) <= (1.0 / PPQN);
-	}
-
-	inline bool operator==(int beats) const {
-		/* Acceptable tolerance is 1 tick. */
-		return fabs(_time - beats) <= (1.0 / PPQN);
-	}
-
-	inline bool operator!=(const MusicalTime& b) const {
-		return !operator==(b);
-	}
-
-	inline bool operator<(const MusicalTime& b) const {
-		/* Acceptable tolerance is 1 tick. */
-		if (fabs(_time - b._time) <= (1.0 / PPQN)) {
-			return false;  /* Effectively identical. */
-		} else {
-			return _time < b._time;
-		}
-	}
-
-	inline bool operator<=(const MusicalTime& b) const {
-		return operator==(b) || operator<(b);
-	}
-
-	inline bool operator>(const MusicalTime& b) const {
-		/* Acceptable tolerance is 1 tick. */
-		if (fabs(_time - b._time) <= (1.0 / PPQN)) {
-			return false;  /* Effectively identical. */
-		} else {
-			return _time > b._time;
-		}
-	}
-
-	inline bool operator>=(const MusicalTime& b) const {
-		return operator==(b) || operator>(b);
-	}
-
-	inline bool operator<(double b) const {
-		/* Acceptable tolerance is 1 tick. */
-		if (fabs(_time - b) <= (1.0 / PPQN)) {
-			return false;  /* Effectively identical. */
-		} else {
-			return _time < b;
-		}
-	}
-
-	inline bool operator<=(double b) const {
-		return operator==(b) || operator<(b);
-	}
-
-	inline bool operator>(double b) const {
-		/* Acceptable tolerance is 1 tick. */
-		if (fabs(_time - b) <= (1.0 / PPQN)) {
-			return false;  /* Effectively identical. */
-		} else {
-			return _time > b;
-		}
-	}
-
-	inline bool operator>=(double b) const {
-		return operator==(b) || operator>(b);
-	}
-
-	MusicalTime operator+(const MusicalTime& b) const {
-		return MusicalTime(_time + b._time);
-	}
-
-	MusicalTime operator-(const MusicalTime& b) const {
-		return MusicalTime(_time - b._time);
-	}
-
-	MusicalTime operator+(double d) const {
-		return MusicalTime(_time + d);
-	}
-
-	MusicalTime operator-(double d) const {
-		return MusicalTime(_time - d);
-	}
-
-	MusicalTime operator-() const {
-		return MusicalTime(-_time);
-	}
-
-	template<typename Number>
-	MusicalTime operator*(Number factor) const {
-		return MusicalTime(_time * factor);
-	}
-
-	MusicalTime& operator+=(const MusicalTime& b) {
-		_time += b._time;
-		return *this;
-	}
-
-	MusicalTime& operator-=(const MusicalTime& b) {
-		_time -= b._time;
-		return *this;
-	}
-
-	double   to_double()              const { return _time; }
-	uint64_t to_ticks()               const { return lrint(_time * PPQN); }
-	uint64_t to_ticks(uint32_t ppqn)  const { return lrint(_time * ppqn); }
-
-	uint32_t get_beats() const { return floor(_time); }
-	uint32_t get_ticks() const { return (uint32_t)lrint(fmod(_time, 1.0) * PPQN); }
-
-	bool operator!() const { return _time == 0; }
-
-	static MusicalTime min()  { return MusicalTime(DBL_MIN); }
-	static MusicalTime max()  { return MusicalTime(DBL_MAX); }
-	static MusicalTime tick() { return MusicalTime(1.0 / PPQN); }
-
-private:
-	double _time;
-};
-
-extern LIBEVORAL_API const MusicalTime MaxMusicalTime;
-extern LIBEVORAL_API const MusicalTime MinMusicalTime;
-
 /** Type of an event (opaque, mapped by application) */
 typedef uint32_t EventType;
 
-/*
-  TIL, several horrible hours later, that sometimes the compiler looks in the
-  namespace of a type (Evoral::MusicalTime in this case) for an operator, and
-  does *NOT* look in the global namespace.
-
-  C++ is proof that hell exists and we are living in it.  In any case, move
-  these to the global namespace and PBD::Property's loopy
-  virtual-method-in-a-template will bite you.
-*/
-
-inline std::ostream&
-operator<<(std::ostream& os, const MusicalTime& t)
-{
-	os << t.to_double();
-	return os;
-}
-
-inline std::istream&
-operator>>(std::istream& is, MusicalTime& t)
-{
-	double beats;
-	is >> beats;
-	t = MusicalTime(beats);
-	return is;
-}
-
 } // namespace Evoral
 
 namespace PBD {
@@ -246,16 +49,7 @@ namespace PBD {
 		LIBEVORAL_API extern uint64_t Sequence;
 		LIBEVORAL_API extern uint64_t Note;
 		LIBEVORAL_API extern uint64_t ControlList;
-		LIBEVORAL_API extern uint64_t MusicalTime;
 	}
 }
 
-namespace std {
-	template<>
-	struct numeric_limits<Evoral::MusicalTime> {
-		static Evoral::MusicalTime min() { return Evoral::MusicalTime::min(); }
-		static Evoral::MusicalTime max() { return Evoral::MusicalTime::max(); }
-	};
-}
-
 #endif // EVORAL_TYPES_HPP
diff --git a/libs/evoral/src/Event.cpp b/libs/evoral/src/Event.cpp
index b874c37de4..66e45ab2ad 100644
--- a/libs/evoral/src/Event.cpp
+++ b/libs/evoral/src/Event.cpp
@@ -155,7 +155,7 @@ Event<Timestamp>::set_original_time (Timestamp t)
 	
 #endif // EVORAL_EVENT_ALLOC
 
-template class Event<Evoral::MusicalTime>;
+template class Event<Evoral::Beats>;
 template class Event<double>;
 template class Event<int64_t>;
 
diff --git a/libs/evoral/src/MIDIEvent.cpp b/libs/evoral/src/MIDIEvent.cpp
index 66a97f73e4..4985f66cf4 100644
--- a/libs/evoral/src/MIDIEvent.cpp
+++ b/libs/evoral/src/MIDIEvent.cpp
@@ -102,7 +102,7 @@ MIDIEvent<Time>::to_xml() const
 
 #endif // EVORAL_MIDI_XML
 
-template class MIDIEvent<Evoral::MusicalTime>;
+template class MIDIEvent<Evoral::Beats>;
 
 } // namespace Evoral
 
diff --git a/libs/evoral/src/Note.cpp b/libs/evoral/src/Note.cpp
index 93c0a90478..7e4f58d73f 100644
--- a/libs/evoral/src/Note.cpp
+++ b/libs/evoral/src/Note.cpp
@@ -108,7 +108,7 @@ Note<Time>::operator=(const Note<Time>& other)
 	return *this;
 }
 
-template class Note<Evoral::MusicalTime>;
+template class Note<Evoral::Beats>;
 
 } // namespace Evoral
 
diff --git a/libs/evoral/src/OldSMF.cpp b/libs/evoral/src/OldSMF.cpp
index 0cee749c9c..eef61e332b 100644
--- a/libs/evoral/src/OldSMF.cpp
+++ b/libs/evoral/src/OldSMF.cpp
@@ -364,6 +364,6 @@ SMF<Time>::write_var_len(uint32_t value)
 	return ret;
 }
 
-template class SMF<Evoral::MusicalTime>;
+template class SMF<Evoral::Beats>;
 
 } // namespace Evoral
diff --git a/libs/evoral/src/Sequence.cpp b/libs/evoral/src/Sequence.cpp
index a77e3c94be..10b7e31b79 100644
--- a/libs/evoral/src/Sequence.cpp
+++ b/libs/evoral/src/Sequence.cpp
@@ -1404,6 +1404,6 @@ Sequence<Time>::dump (ostream& str) const
 	str << "--- dump\n";
 }
 
-template class Sequence<Evoral::MusicalTime>;
+template class Sequence<Evoral::Beats>;
 
 } // namespace Evoral
diff --git a/libs/evoral/src/TimeConverter.cpp b/libs/evoral/src/TimeConverter.cpp
index 0d39087e7c..e1e4b8231f 100644
--- a/libs/evoral/src/TimeConverter.cpp
+++ b/libs/evoral/src/TimeConverter.cpp
@@ -45,6 +45,6 @@ IdentityConverter<A,B>::from(B b) const
 
 template class IdentityConverter<double, framepos_t>;
 template class TimeConverter<double, framepos_t>;
-template class TimeConverter<Evoral::MusicalTime, framepos_t>;
+template class TimeConverter<Evoral::Beats, framepos_t>;
 
 } // namespace Evoral
diff --git a/libs/evoral/src/types.cpp b/libs/evoral/src/types.cpp
index 80801dcdea..50c2975d3d 100644
--- a/libs/evoral/src/types.cpp
+++ b/libs/evoral/src/types.cpp
@@ -22,8 +22,8 @@
 
 namespace Evoral {
 
-const double      MusicalTime::PPQN = 1920.0;
-const MusicalTime MaxMusicalTime    = Evoral::MusicalTime(DBL_MAX);
-const MusicalTime MinMusicalTime    = Evoral::MusicalTime(DBL_MIN);
+const double Beats::PPQN = 1920.0;
+const Beats  MaxBeats    = Evoral::Beats(DBL_MAX);
+const Beats  MinBeats    = Evoral::Beats(DBL_MIN);
 
 }
diff --git a/libs/evoral/test/SMFTest.cpp b/libs/evoral/test/SMFTest.cpp
index 9bbe021947..d42ee26dff 100644
--- a/libs/evoral/test/SMFTest.cpp
+++ b/libs/evoral/test/SMFTest.cpp
@@ -45,25 +45,25 @@ SMFTest::takeFiveTest ()
 	smf.seek_to_start();
 
 	uint64_t time = 0; /* in SMF ticks */
-	Evoral::Event<Evoral::MusicalTime> ev;
+	Evoral::Event<Evoral::Beats> ev;
 
 	uint32_t delta_t = 0;
 	uint32_t size    = 0;
 	uint8_t* buf     = NULL;
 	int ret;
 	while ((ret = smf.read_event(&delta_t, &size, &buf)) >= 0) {
-		ev.set(buf, size, Evoral::MusicalTime());
+		ev.set(buf, size, Evoral::Beats());
 		time += delta_t;
 
 		if (ret > 0) { // didn't skip (meta) event
 			//cerr << "read smf event type " << hex << int(buf[0]) << endl;
-			ev.set_time(Evoral::MusicalTime::ticks_at_rate(time, smf.ppqn()));
+			ev.set_time(Evoral::Beats::ticks_at_rate(time, smf.ppqn()));
 			ev.set_event_type(type_map->midi_event_type(buf[0]));
 			seq->append(ev, next_event_id ());
 		}
 	}
 
 	seq->end_write (Sequence<Time>::Relax,
-	                Evoral::MusicalTime::ticks_at_rate(time, smf.ppqn()));
+	                Evoral::Beats::ticks_at_rate(time, smf.ppqn()));
 	CPPUNIT_ASSERT(!seq->empty());
 }
diff --git a/libs/evoral/test/SMFTest.hpp b/libs/evoral/test/SMFTest.hpp
index 6e42b6f7b3..94172c62c8 100644
--- a/libs/evoral/test/SMFTest.hpp
+++ b/libs/evoral/test/SMFTest.hpp
@@ -57,7 +57,7 @@ class SMFTest : public CppUnit::TestFixture
 	CPPUNIT_TEST_SUITE_END();
 
 public:
-	typedef Evoral::MusicalTime Time;
+	typedef Evoral::Beats Time;
 
 	void setUp() {
 		type_map = new DummyTypeMap();
diff --git a/libs/evoral/test/SequenceTest.cpp b/libs/evoral/test/SequenceTest.cpp
index f6a8363f4d..39afcd3095 100644
--- a/libs/evoral/test/SequenceTest.cpp
+++ b/libs/evoral/test/SequenceTest.cpp
@@ -75,7 +75,7 @@ SequenceTest::iteratorSeekTest ()
 	}
 
 	bool on = true;
-	for (Sequence<Time>::const_iterator i = seq->begin(Evoral::MusicalTime(600)); i != seq->end(); ++i) {
+	for (Sequence<Time>::const_iterator i = seq->begin(Evoral::Beats(600)); i != seq->end(); ++i) {
 		if (on) {
 			CPPUNIT_ASSERT(((const MIDIEvent<Time>&)*i).is_note_on());
 			CPPUNIT_ASSERT_EQUAL(i->time(), Time((num_notes + 6) * 100));
diff --git a/libs/evoral/test/SequenceTest.hpp b/libs/evoral/test/SequenceTest.hpp
index d8e0406100..da1991efc8 100644
--- a/libs/evoral/test/SequenceTest.hpp
+++ b/libs/evoral/test/SequenceTest.hpp
@@ -113,7 +113,7 @@ class SequenceTest : public CppUnit::TestFixture
 	CPPUNIT_TEST_SUITE_END ();
 
 public:
-	typedef MusicalTime Time;
+	typedef Beats Time;
 	typedef std::vector< boost::shared_ptr< Note<Time> > > Notes;
 
 	void setUp () {
@@ -125,7 +125,7 @@ public:
 		for (int i = 0; i < 12; i++) {
 			test_notes.push_back(
 				boost::shared_ptr<Note<Time> >(
-					new Note<Time>(0, MusicalTime(i * 100), MusicalTime(100), 64 + i, 64)));
+					new Note<Time>(0, Beats(i * 100), Beats(100), 64 + i, 64)));
 		}
 	}
 
diff --git a/libs/midi++2/midnam_patch.cc b/libs/midi++2/midnam_patch.cc
index 55e7ac1898..e1b3007bd3 100644
--- a/libs/midi++2/midnam_patch.cc
+++ b/libs/midi++2/midnam_patch.cc
@@ -97,7 +97,7 @@ Patch::get_state (void)
 	node->add_property("Name",   _name);
 
 	/*
-	typedef std::list< boost::shared_ptr< Evoral::MIDIEvent<Evoral::MusicalTime> > > PatchMidiCommands;
+	typedef std::list< boost::shared_ptr< Evoral::MIDIEvent<Evoral::Beats> > > PatchMidiCommands;
 	XMLNode* commands = node->add_child("PatchMIDICommands");
 	for (PatchMidiCommands::const_iterator event = _patch_midi_commands.begin();
 	    event != _patch_midi_commands.end();