The October 13, 2015 release of the RDA Toolkit included minimal revisions to MLA’s Best Practices.
One revision affects 2.15.3 (Plate Number for Music). When a plate number on a score has an additional number (often after a dash) corresponding to the number of pages or plates, it is to be recorded as part of the plate number instead of ignored. The plate number may optionally also be recorded without this additional number. For example:
028 22 23009-11 $b Carl Fischer
028 20 23009 $b Carl Fischer
Further revision was done to 7.13.3 (Form of Musical Notation). The August release included new guidance about MARC encoding for multiple designations of form of musical notation as well as new examples. The October release adds new guidance covering details of form of musical notation as well as new examples. There is now sufficient guidance for cases such as chord symbols, chord diagrams, verbal instructions, etc.
Typos and various other errors were corrected both in the BPs themselves (accessible only via the RDA Toolkit) and in the supplements (accessible via the MLA CMC website).
Thanks to everyone who was involved in this effort.
The August release included new guidance for 3.16.3 (Recording Medium) that was not publicized. Recording medium (“optical,” “magnetic,” etc.) should now be recorded as applicable, in MARC 344 $b. As an example, the full array of 34X values for a typical CD with stereo playback is as follows:
344 digital $b optical $g stereo $2 rda
347 audio file $b CD audio $2 rda