diff --git a/mopidy/models/__init__.py b/mopidy/models/__init__.py
index 7cf8cc77..e4e8528a 100644
--- a/mopidy/models/__init__.py
+++ b/mopidy/models/__init__.py
@@ -30,6 +30,11 @@ class Ref(ImmutableObject):
     #: The object name. Read-only.
     name = fields.String()
 
+    #: The object type, e.g. "artist", "album", "track", "playlist",
+    #: "directory". Read-only.
+    type = fields.Identifier()  # TODO: consider locking this down.
+    # type = fields.Field(choices=(ALBUM, ARTIST, DIRECTORY, PLAYLIST, TRACK))
+
     #: Constant used for comparison with the :attr:`type` field.
     ALBUM = 'album'
 
@@ -45,10 +50,6 @@ class Ref(ImmutableObject):
     #: Constant used for comparison with the :attr:`type` field.
     TRACK = 'track'
 
-    #: The object type, e.g. "artist", "album", "track", "playlist",
-    #: "directory". Read-only.
-    type = fields.Field(choices=(ALBUM, ARTIST, DIRECTORY, PLAYLIST, TRACK))
-
     @classmethod
     def album(cls, **kwargs):
         """Create a :class:`Ref` with ``type`` :attr:`ALBUM`."""
diff --git a/tests/models/test_models.py b/tests/models/test_models.py
index c9c91ba1..bdfd1896 100644
--- a/tests/models/test_models.py
+++ b/tests/models/test_models.py
@@ -113,7 +113,7 @@ class RefTest(unittest.TestCase):
 
     def test_repr_without_results(self):
         self.assertEqual(
-            "Ref(name=u'foo', type=u'artist', uri='uri')",
+            "Ref(name=u'foo', type='artist', uri='uri')",
             repr(Ref(uri='uri', name='foo', type='artist')))
 
     def test_serialize_without_results(self):