Digitization of sound recordings

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 Mežnaric Karafin - Zagreb Academy of
music, Library alexm_at_muza.hr
2

• 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

3

• 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)

4

• Development of the sound recording techniques
• begun with Edisons 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...

5

• 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 (Medimurje)
  original cylinders stored in Phonogrammarchiv

6

• 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

7

• 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
  Medimurje
• analogue magnetic tape recording remained
  primary field recording tecnique by the eighties
  (when digital recording technology was perfected)

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• 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

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• 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

10

• 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)

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• 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 long-term preservation
• for preservation and storage of sound recordings
  they recommend re-recording of endangered
  materials on analogue magnetic tapes

12

• 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
• Smith (1999)
• digitization is primarily a method of providing
  access to rare, endangered, or distance materials
  not permanent solution for preservation

13

• 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

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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
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• 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)

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• 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

17

• 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

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• 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

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• 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

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• 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 /mono-stereo/ and equalization
  standards,...)
• Data about original tapes, restoration
  procedures, replay and transfer parameters must
  be documented for the future reference!

21

• 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

22

• 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

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• 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!

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• 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

25

• 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

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• 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

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• 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)

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• 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

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• 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

30

• 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

31

• 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

32

• 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

33

• 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

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• 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 R-DAT
• systematic digitization begun in year 2000,
  according to IASA-TC 04

35

• 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

36

• 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

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• 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

38

• 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

39

• 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

40

• 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

41

• 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