A brief overview of some of the changes from AACR2 to RDA

content, media, and carrier type

From Kathy Glennan, MLA-L, 1/17/2014

• RDA generally eschews abbreviations. The primary exceptions are for:
  • Units of measurement
  • Abbreviations that are regularly used in resources and are commonly understood by users (e.g., "SATB", "op.")
  • Abbreviations that a resource uses to identify itself (e.g., "BWV" instead of "Bach-Werke-Verzeichnis")

Abbreviations are used only when they appear on the resource. The exceptions are no. and op. (which will be used the same way as they were in AACR2: in the title area, abbreviate only when abbreviated on the item; abbreviate in access points), thematic index numbers, voice range (SATB, etc.), and units of measurements.
     Use "in." for inches; however, "cm" is no longer considered to be an abbreviation
Use "stereo" and "mono" (also no longer considered to be abbreviations), but spell out other terms ("quadrophonic," etc.)

Metric units:
AACR2: they are considered abbreviations and are followed by a full stop (e.g., cm.)
RDA: they are treated as symbols and are not followed by a full stop (e.g., cm).

Examples of changes to abbreviations used in dates [13] in authorized access points representing persons (formerly known as name headings)

New to RDA:
Capitalization [15]: RDA Appendix A: LC policy is to follow the capitalization on the resource or follow the instructions in Appendix A.
Diacritics [16]: Transcribe when they appear; not necessary to add them when they are omitted from the resource.
Abbreviations [10]: RDA Appendix B: Transcribe as found on the RDA preferred source; otherwise do not use abbreviations

Other things:
Parallel titles [17] may be taken from anywhere on the resource, and are not enclosed in brackets
   ° However, other title information [18] must be taken from the same source as the title proper
Statement of responsibility [19] may be taken from anywhere on the resource
   ° Transcribe title, terms of address, etc.
   ° Transcribe all persons named, even when there are four or more
Edition statement:
   ° Abbreviations are used only when they appear on the resource
   ° Use the form of numbering (e.g., Arabic, roman, etc.) that appear on the resource

Examples
AACR2 1.0F
245 10 ‡a Morton Feldmans Untiteled [sic] composition für Cello und Klavier
246 3  ‡a Morton Feldmans Untitled composition für Cello und Klavier

RDA 1.7.9, 2.3.1.4
245 10 ‡a Morton Feldmans Untiteled composition für Cello und Klavier
246 3  ‡i Title should read: ‡a Morton Feldmans Untitled composition für Cello und Klavier

AACR2 1.0F
245 00 ‡a Horn sonat[a]s
246 3  ‡a Horn sonats

RDA 1.7.9, 2.3.1.4
245 00 ‡a Horn sonats
246 3  ‡i Title should read: ‡a Horn sonatas

Example
Title appears on the resource as
...Huésped de las nieblas...
...Guest from the mists...
for flute and piano

AACR2 1.1B1F
245 10 ‡a --Huésped de las nieblas-- = ‡b --Guest from the mists-- : for flute and piano

RDA 1.7.3
245 10 ‡a ...Huésped de las nieblas... = ‡b ...Guest from the mists... : for flute and piano

Abbreviations [10] are not used unless they appear on the resource.

Place of publication: if more than one, only the first is required (2.8.2)
   ° Include all hierarchies of place, e.g., New Haven, CT, USA
   ° No requirement to include place in the US if the publisher is not in the US
Publisher name: if more than one, on the first is required (2.8.4)
   ° Use the full name as found on the resource, e.g., Theodore Presser Company, Hildegarde Publishing Company
   ° Include all corporate hierarchies of the name of publisher
Date of publication: record the date as found on the resource
   ° LCPS 1.8.2 (first alternative) says to transcribe roman numerals and not convert to Arabic

Place, name, and/or date of publication not identified on resource:
   ° AACR2: [S.l.], [s.n.], [n.d.]
   ° RDA: [place of publication not identified], [publisher not identified], [date of publication not identified]
      ° LCPS instruction strongly encourages: supply a place of publication in brackets or date in brackets
      ° Each subfield is separately bracketed: D1.2.1: When adjacent elements within one area are to be enclosed in square brackets, enclose each in its own set of square brackets.

from: RDA Basics [23] (PPT)

Publication dates and copyright (©)/phonogram () dates [24]

If the date of publication is unknown, use [Date of publication not identified] or an estimated date in brackets, with a question mark, if necessary.
Copyright/phonogram date is not required if a publication date is known. However, for music materials, it is strongly suggested that copyright/phonogram dates are included, even when they are the same as the publication date.
   ° Record the latest copyright date; for recordings, prefer dates over © dates.

Use the appropriate term, which may be a term from the carrier type list (3.3.1.3 [8]) or a general term (3.4.1.3)

Notated music:
Some terms are no longer used.

Three new fields (336, 337, 338) collectively replace the General material designation (245 ‡h)
See Content, Media, and Carrier [27] (RDA 6.9, 3.2, 3.3 & MARC 336-338)

Authorized access points comprise
   ° preferred name of the creator (if applicable)
   ° preferred title of work (6.2.1 [39], 6.14 [40], 6.28.1.1-6.28.1.8 [41])
   ° additional elements to differentiate among other works/expressions (6.28.1.9-6.28.1.11 [42])

Differences from AACR2:
   ° no equivalent to AACR2's "works of mixed responsibility"
   ° "work(s)" in RDA refers to both individual works and compilations
   ° medium of performance in access point can contain more than three elements
   ° standard chamber combinations (e.g., string quartet, piano trio, etc.) are no longer used
   ° use "cello" not "violoncello"
   ° spell out "acc." "arr." and "unacc."
   ° fewer restrictions on recording key
   ° librettos and operas are considered separate works
Source: RDA and Sound Recordings—A Cataloging Workshop: Cataloging with RDA—Sound Recordings [3]