Transcript Slide 1

Digitization of sound recordings
as an example for preservation
of oral and music folklore heritage
Basic principles and two examples from practice:
Zagreb Institute for ethnology and folklore research
Vienna Phonogrammarchiv
Aleksandra Mežnarić Karafin - Zagreb Academy of music, Library
[email protected]
Sound recordings are unique witnesses of
human social and cultural history starting fom
the end of 19th century
• They can preserve:
speeches, lectures, interviews
musical / speech performances
musical and oral folklore traditions
• They have great documentary value
• They are essential in scentific studies that require
field research – linguistics, anthropology, folklore
research
Folklore:
• communication process embodied in orally transmitted
forms of cultural expression of all segmets of society
Recordings from field research are irreplaceable:
• they contain spontaneous, unrepeatable elements which
could not be documented and preserved in written notes
• large quantities of filed recordings on endangered carrier
– wax cylinders, steel wire, analog magnetic tape
• their significance is not always recognized
• projects: TAPE, PRESTO, UNESCO Memory of the world
program, U.S. Congress National Recording Preservation
Act (2000)
Development of the sound recording techniques:
• begun with Edison’s invention of the phonograph in
1877
• improved, portable version of the phonograph vas
introduced in 1880 (recording media - wax cylinder)
• influenced the scope, focus and methods of the field
research of traditional culture, also in linguistics,
anthropology, zoology...
First phonograph field recordings:
• 1890 J. W. Fawkes, ethnologist
• 1901 Milan Rešetar, linguist (Slavic languages
research for Phonogrammarchiv)
• B. Bártok i Z. Kodály – recordings of traditional
music of Hungary and Rumania
• in the period of 1920-1930 – B. Širola and M.
Gavazzi – recordings form Kotoriba (Međimurje) –
original cylinders stored in Phonogrammarchiv
Magnetic recording technique
• basic principles yet in 1878 (O. Smith), perfected
during the World War II
• sound carrier evolved fom steel wire into magnetic
tape
• widely spread in the fifties - transporatble
recording units with bateries – important for the
filedwork
• in Vienna Phonogrammarchiv introduced in 1951, fom
1954 portable recorders in field research
• first recordings for IEF in 1954 – ethnomusicologist
Vinko Žganec, filed trip to Međimurje
• analogue magnetic tape recording remained primary
field recording tecnique by the eighties (when digital
recording technology was perfected)
Result :
• large collections of deteriorating sound recordings –
in archives, research institutions all over the world
Significance:
• witnesses of the wanishing traditions
• of the turbulent social and cultural changes
• focus of the scientific research of home institutions
Preservation problems:
• rapid alteration of inovation and obsolescence in every
aspect of the sound recording, reproduction and storage
(new media, obsolete reproduction equipment, no expert
personal)
• sound carriers have shorter life expectance than the
traditional printed material – unstable base materials,
more subject to damage caused by inadequate handling,
storage and replay equipment
To hear those recordings we need:
• physical carrier in good condition – magnetic tapes
are considered endangered storage media
(specially acetate base ones)
• available and functional reproduction equipment –
magnetic tape players are almost obsolete
• knowledge of how to handle that equipment, of
sound / recording format /speed (user need special
knowledge and experience to safely handle an open
reel magnetic tape)
How to preserve sound recording on the carrier
endangered by inevitable deterioration:
• transfer the recording on to new media, or,
• convert the recording to a new format
Approaches:
• in the last decade of 20th century expert associations
(AES, NARA, ARSC) still concerned about use of digital
recording technology and digital storage media for longterm preservation
• for preservation and storage of sound recordings they
recommend re-recording of endangered materials on
analogue magnetic tapes
Ch. A. Paton (1998) reasons against digital technology:
• rapid change /improvement of the technology – rapid
obsolescence of hardware, digital format and storage
media
• lack of consensus regarding sample rate, bit depth
and record format for sound archiving
• questionable stability and durability of the storage
media
A.Smith (1999):
• digitization is primarily a method of providing access
to rare, endangered, or distance materials – not
permanent solution for preservation
E. Cohen (2001) – “distribution is preservation”-relays on
the possibilities that lay in digital domain and networked
environment:
• creating an unlimited number of identical copies without
the loss of original information
• simple distribution of the documents
• web access
• permanent, media independent preservation of digital
content
• “Urgent conversion of analogue recordings into
digital domain is an imperative – to hesitate
means to compromise preservation”
Important:
Preservation of original carriers and original replay
equipment is of same importance:
future development of sound reproduction
technology could enable the transfer of yet
unavailable subtle sound contetnt
Analogue sound recording digitization
standards – basic documents:
• IFLA Guidelines for digitization projects (2002)
• IASA – Technical Committee Standards IASA-TC
03 (2005) - The Safeguarding of the Audio
Heritage: Ethics, Principles and Preservation
Strategy
•IASA-TC 04 (2004) – Guidelines on the Production
and Preservation of Digital Audio bjects
•IASA Task force to establish selection criteria of
analogue and digital audio content for transfer to
data formats for preservation purposes (2003)
Reasons for digitization:
• saving original sound content from endangered carrier /
protection of the original carrier
• easy access – replay equipment for magnetic tapes
became obsolete, complicated for handling, incompetent
user can cause damage to the tape
• providing new services / attracting new users
Basic selection criteria – IFLA Guidelines:
•Content: intellectual value of materials, their historical,
scientific and cultural significance – unique sources must
have priority
•Demand: priority is given to materials in constant
demand
•Condition: fragile and damaged unique materials –
restoration procedures may be needed before the
transfer
Priorities - analogue sound recordings (IASA_TC
03):
• documents in immediate risk / recordings on endangered
media
• documents who are part of an obsolete or commercially
unsupported system
• documents in regular demand
Transfer of analogue recordings:
• for optimal transfer of analogue recording maximum
fidelity during the reproduction of the original must be
ensured
• expert knowledge of original format is required
• availability and optimal adjustment of well maintained
and completely functional replay equipment
Preparation procedures:
• Checking, preparation and cleaning of the original tape
(identification of the tape, establishing tape condition,
eventual damage repair)
• Configuration and calibration of replay equipment
(tape speed setting, defining recording format /monostereo/ and equalization standards,...)
• Data about original tapes, restoration procedures,
replay and transfer parameters must be documented for
the future reference!
Sound recording digitization standards according
to IASA-TC 03:
• sampling frequency / bit rate - 96 kHz /24 bit - archival
sound record standard
• user copy – CD-Audio quality (44,1 kHz/16 bit)
• data reduction (MP3) if needed (network transfer)
• unmodified transfer – analogue signal should be
transferred without modifications – unintended sound
artifacts are important part of sound document
Sound record format for sound archiving:
• widely accepted formats should be chosen
• should support high resolution audio records
• should be transparent – simple coding schemes (PCM),
without data reduction
• should have enclosed metadata about data extraction
procedures
IASA-TC 03 recommends:
• WAVE (.wav)
• Broadcast Wave Format (.bwf)
• Audio Interchange File Format (.aiff),
• PCM or LPCM coding schemes
 MP3 only for access copies or web streaming – not
appropriate for long-term preservation!
Principles of digital sound archiving (IASA-TC 03):
• each digital copy must be free of uncorrectable errors
• each carrier must be regularly checked for data integrity
• digital content must be copied before:
uncorrectable errors occur (refreshment)
carriers, formats, hardware becomes obsolete
(migration)
• at least two preservation copies
• additional access copies – should not be kept in the same
location as preservation copies
Digital storage media:
• magnetic and optical media
• lifetime and stability depending on conditions of their
use and storage
• subject to hardware and format obsolescence
• mostly used: R-DAT, CD-R, DLT and LTO magnetic
tapes
• R-DAT – considered obsolete
• raising concern about use of CD-R and DVD as digital
target formats for archives
• rapid changes in storage media, format, hardware
and software
Solution for long term preservation:
repositories based on OAIS model, or Digital Mass Storage
System (DMSS)
• automated, media independent approach
• automated systems for storage, management,
maintaining and integrity check of digital data,
• preservation and distribution of digital objects with
embedded metadata
• large financial investments needed – out of reach to
smaller institutions and archives
Metadata
• indispensable for finding, control and usage of digital
documents
• descript ional, administrative and structural metadata
• preservation metadata mandatory at assessment of
technical parameters of the recording – data about original
carrier, format and preservation, reproduction equipment
and its parameters
• data about digital format, resolution
• most used – MARC bibliographic record and Dublin Core
Metadata Element Set
• standalone / embedded (Standard Generalized Markup
Language)
Institute for ethnology and folklore research:
• sound recording collection is a part of Documentation
collection – documents are result of scientific research
activities of IEF – since 1948
• unique documents regarding Croatian traditional culture
of 20th century, culture of other nationalities in Croatia
and Croats abroad
• from 1991 status of cultural monument “0” and “I”
category
• sound recording collection – 3300 magnetic tapes (PVC
based) – 4000 hours of recorded material
• in the nineties, during the war tapes stored in the
cellar of old building where IEF was located
• in 1995. first signs of deterioration were
discovered (mould)
• after consultation with audio engineer of Croatian
radio and Samofix company digitization - transfer
of recordings from magnetic tapes to audio CD was
initiated
• never defined as a official project
Project objectives (Samofix d.o.o. proposal):
• to make recordings available for a larger number of
users
• easier browsing thru CD content
• technical make-up – to increase quality of the
recordings, and to make them “clearer”
• choice of storage media (CD-R) based on its wide
acceptance, practical use, and then still unconfirmed
assumptions about its durability and life expectancy
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restoration procedures were not documented, neither
procedures of “cleaning of sound content” and “removal
of useless situations”
restoration procedures, transfer of original recordings,
choice of digital resolution and digital record storage
media defined only in Samofix d.o.o. project proposal
(1996)
in nine years recordings from 521 tape were transferred
to 659 CD-s
digital record resolution 44 kHz/ 16 bit
audio CD .cda digital sound format
two identical copies – archival / user, stored in the same
place as the tapes
Basic description in computer database (File
Maker Pro):
• data about author of recording, location, year, title broadly defines the content, and detailed list of
recorded content
• no information about original tape, recording
equipment, transfer procedures
• not based on any accepted metadata scheme
Digitization of sound collection:
• carried out with difficulties in financing – partially IEF,
and Ministry of culture (until 2003)
• one of the first in this part of Europe
• some solutions are problematic in long-term
• in Croatia – important, ground-braking initiative of small
unprofitable cultural institution
• in the future – necessary to revise current basic
principles according to internationally accepted standards
Phonogrammarchiv of Austrian Academy of
Sciences
• the oldest sound archive in the world (1899), significant
Historic collection
• sound collection has 43074 recordings on magnetic tapes
(acetate, PVC, polyester)
• tapes generally in good condition, fully functional
reproduction equipment
• digitization started in 1995 – tapes first converted to RDAT
• systematic digitization begun in year 2000, according to
IASA-TC 04
• archive digitizes parts of its one collection, and
collections of other archives and institutions (Quellmalz
collection, 2007, Memory of the world Program)
• from the beginning digital resolution of 96 kHz/ 24 bit
was used,
• WAVE (.wav) sound record format
original sound record was not modified in any way –
digital copy is real copy of the original
•
• physical restoration of the tapes, when needed
• archival sound record and complete additional
documentation stored in two identical copies on LTO3
magnetic tapes
• for storing, access and manipulation – combination of
server, LTO Juke Box and manual manipulation is used
• user copies available online in MP3 format
• metadata: Dublin Core Metadata Element Set,
supplemented by IASA cataloguing rules
Conclusion:
• digitization of field recordings on analogue magnetic
tapes - preservation of valuable folklore heritage
• value of sound recordings internationally recognized U. S. Congress National Recording Preservation Act
(2000)
• Projects (TAPE, PRESTO, UNESCO Memory of the
world program)
• standards defined by IFLA, IASA, AES
• field recordings as an example of material with
specific function and documentary value
• only a small part of comprehensive sound heritage
• in Croatia – problem is neglected, interest in sound
recordings preservation only recently
• without change in approach – because lack of interest
and knowledge significant part of cultural heritage will
be irreversibly lost
IEF and Phonogrammarchiv:
In common:
• scientific research of folklore an significant collections
of filed recordings on magnetic tapes
Different:
• primary function and priorities, staff profile, technical
equipment and financial possibilities
Result of digitization
IEF
• easy access, preservation of original tape, but not
completely original, unmodified sound information
• undocumented modifications – questionable fidelity of
digital record
Phonogrammarchiv
• preserved original sound documents
• expert standards were followed in all aspects of
digitization process
• ideal conditions for conducting complex digitization
projects
Steps for action:
• encourage persons on responsible positions in
institutions who collect this material to recognize its value
as a part of cultural heritage
• educating experts in the field of preservation and
archiving of sound materials
• defining projects according to international standards
and recommendations
• ensuring financial support from responsible state
administrative bodies, international projects and programs