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The sound recordings preservation and access program at Berea College's Hutchins Library began in 2006.
The program's focus is on Berea's collections of noncommercial recordings that document Appalachian history and culture and the history of Berea College. The recordings are especially strong in the areas of traditional music, religious expression, folklore, radio programs, College events, and oral history. Preserving these one-of-a-kind recordings is an urgent need because the open reel and cassette tape on which they are recorded is nearing the point of being unplayable due to age and scarceness of proper playback equipment.
In accomplishing the task of accurately and reliably preserving
the recordings for the very long term, the program is guided by
the recommendations of the International Association of Sound and
Audiovisual Archives as set forth in IASA-TC04
Guidelines on the Production and Preservation of Digital Audio
Objects: Standards,
Recommended Practices, and Strategies.
Key elements of Berea’s preservation and access efforts
include converting the original recordings to high resolution
digital files, providing CD listening copies for Library use, and
storing the digital files on a dedicated server which is backed
up at remote locations. A searchable online database of collection
contents and selected audio files are available through Hutchins
Library’s Sound Archives Web Page.
Hutchins Library’s Audio Preservation
Program Details
Audio Formats
Open Reel Tape
Cassette Tape
Playback Equipment & Procedures
Analog-to-Digital Process
Digital File Formats
Digital Preservation
Digital Access
Links to Related Sources
Audio Formats
Hutchins Library’s non-commercial sound recording collections
consist of some 12,000 items. Those at highest risk are open
reel and cassette audio tape, lacquer discs, and digital audio
tape
(DAT). Each format presents different requirements in terms of
physical handling, playback equipment and procedures.
Open Reel Tape 
The Library has approximately 4,500 open reel tapes. About 20%
of them have an acetate base with the remainder being polyester.
There are also a few paper-based tapes. Many of the open reel tapes
are recordings of Berea College’s annual Celebration of Traditional
Music dating from 1974. Other open reel tape collections include
the folklore and traditional music field recordings of Leonard
Roberts, William
Tallmadge, Bruce
Greene, John
Harrod, and Barbara
Kunkle and range in date from the early 1950s through the 1970s.
Acetate-based open reel tape is less stable than polyester and
represents a higher priority for preservation
copying. Acetate tape is eight times more sensitive to moisture
in the air than
polyester, leading to tape pack problems such as linear expansion,
transverse warping (curling or cupping), windowing, etc.
 Vinegar
Syndrome is another problem that may be found with acetate tape.
This condition, which is most common in acetate photographic film,
is an autocatalytic decomposition process that produces acetic
acid as a byproduct. Once started, the decomposition continues
at an ever-accelerated rate. Archivists have recently identified
Kodak audio tape from the 1960s as susceptible to this condition.
 Some
polyester tape dating from the mid-1970s to around 1990 is affected
by what is known as Sticky Shed Syndrome. This condition is caused
by breakdown of the tape binder by hydrolysis which leads to massive
shedding and squealing when playing. Many of these tapes can be
restored for playback through a heat treatment process, commonly
called “baking,” that is now widely used in audio preservation
work. Once baked, the tape must be transferred within a week or
two before it begins reverting back to the sticky shed condition.
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Cassette Tape
 The Library has approximately 3,500 non-commercial audiocassettes
dating from the 1960s through the 1990s. Although once widely used
for its convenience and economy, audiocassette tape is universally
regarded as undependable for long-term stability and is a high
priority for preservation copying. Older cassette tapes, particularly
those from the 1970s and before, are often exhibiting preservation
problems such as squealing and shedding due to loss of lubricant.
While these symptoms are similar to those of Sticky Shed Syndrome,
appropriate corrective measures are quite different and definitely
do not include baking.
Playback Equipment and Procedure
The aim of preservation copying is to obtain the highest quality,
most accurate representation of the aging original recording possible.
For this reason preservation work at Berea is done with professional-level
playback equipment that is properly calibrated and maintained.
Equipment used in the Library’s sound preservation studio
which is specially designed for critical listening, include a Studer
A807 for open reel tapes and a Tascam 122MkIII for audiocassettes.
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Tascam 122Mkll |
There are several sets of
technical procedures necessary for successful
preservation copying of archival sound recordings.
Among these are basic audio engineering methods along with techniques
essential to optimal, accurate playback of aging tapes.
The use of appropriate procedures makes a measurable, significant
difference in achieving the most accurate representation possible
of the original recording. Included among these procedures are
visual inspection, slow winding, replacing slotted reels, acid-free
paper leaders, proper tape track configuration and playback speed,
playback head azimuth adjustments and reproduction alignments.
Analog-to-Digital Process
For preservation, analog-to-digital conversion (ADC) should be
handled by a converter separate from the computer, according to
best practices document, IASA TC-04
Guidelines on the Production and Preservation of Digital Audio
Objects. The associated sound
card should then be capable of passing a digital stream without
modification.
Berea College uses a Mytek Digital USA Stereo96 ADC/DAC in tandem
with a Lynx Studio Technology LynxONE PCI interface card. Steinberg
WaveLab 6 captures the digital signal as a high-resolution, 24-bit,
96 kHz PCM BWAV
file. A monitor controller system allows for audio monitoring of
pre- and post-digital conversion signal to guard against introduction
of digital artifacts. The entire signal chain, both balanced analog
and AES digital, uses Monster Cable Prolink interconnects.
Digital
File Formats
According to IASA TC-03 The Safeguarding of the Audio Heritage:
Ethics, Principles and Preservation Strategy, preservation transfer
should produce master files that are unmodified, "without
subjective alterations or improvements."
Creating and storing an unaltered, unmodified digital file means
no editing of content. Every second on the source recording, no
matter how irrelevant, is transferred in order to obtain a full,
authentic representation of the original recording. This preserves
content that future researchers may find important in ways
that we cannot anticipate today. In addition, the original sound
field, whether stereo or mono, is preserved in the master archival
file.
Berea’s master archival sound files are 24-bit, 96 kHz PCM
encoded BWAV files, more than twice the resolution of standard
CD audio. This ensures that the full range of reproduced material
is captured and preserved with utmost accuracy.
Derivative audio files are created for any form of editing, signal
processing, or other alterations from the original preservation
file. This includes making reference CDs for in-house listening,
and encoding MP3 files for online access through the Sound Archives
Web Page.
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Digital Preservation
Once high-resolution, unaltered archival master files are created,
they are transferred to a dedicated high volume networked storage
server. While this server acts (and even appears on the workstation
desktop) as a huge hard disk drive (HDD), it is really a series
of HDDs set up in a RAID (redundant array of independent disks.)
As a precaution against data loss, the Sound Archives’ server
files are backed up to remote network-attached storage devices
(NAS) by the College’s Information Systems and Services.
Digital Access
Selected portions of the Berea's digitized recordings are
available online via the following resources:
Links to Related Sources
Analog-to-Digital Process
Playback Equipment
Digital File Formats &
Preservation
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