if (!internal_is_music_type (class_name))
programming_error ("Not a music type");
- Stream_event *e = new Stream_event (class_name, mutable_property_alist_);
+ Stream_event *e = new Stream_event
+ (scm_call_1 (ly_lily_module_constant ("ly:make-event-class"), class_name),
+ mutable_property_alist_);
Moment length = get_length ();
if (length.to_bool ())
e->set_property ("length", length.smobbed_copy ());