diff --git a/libs/ardour/ardour/evoral_types_convert.h b/libs/ardour/ardour/evoral_types_convert.h
new file mode 100644
index 0000000000..38d6c61e99
--- /dev/null
+++ b/libs/ardour/ardour/evoral_types_convert.h
@@ -0,0 +1,67 @@
+/*
+    Copyright (C) 2015 Tim Mayberry
+
+    This program 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.
+
+    This program 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 more 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#ifndef ARDOUR_EVORAL_TYPES_CONVERT_H
+#define ARDOUR_EVORAL_TYPES_CONVERT_H
+
+#include "pbd/enum_convert.h"
+
+#include "evoral/Beats.hpp"
+#include "evoral/ControlList.hpp"
+
+namespace PBD {
+
+DEFINE_ENUM_CONVERT(Evoral::ControlList::InterpolationStyle)
+
+template <>
+inline bool to_string (Evoral::Beats beats, std::string& str)
+{
+	return double_to_string (beats.to_double (), str);
+}
+
+template <>
+inline bool string_to (const std::string& str, Evoral::Beats& beats)
+{
+	double tmp;
+	if (!string_to_double (str, tmp)) {
+		return false;
+	}
+	beats = Evoral::Beats(tmp);
+	return true;
+}
+
+template <>
+inline std::string to_string (Evoral::Beats beats)
+{
+	std::string tmp;
+	double_to_string (beats.to_double (), tmp);
+	return tmp;
+}
+
+template <>
+inline Evoral::Beats string_to (const std::string& str)
+{
+	double tmp;
+	string_to_double (str, tmp);
+	return Evoral::Beats (tmp);
+}
+
+} // namespace PBD
+
+#endif // ARDOUR_EVORAL_TYPES_CONVERT_H