Berea College - Hutchins Library

The sound recordings preservation and access program at Berea College’s Hutchins Library has been made possible by a grant from the Anne Ray Charitable Trust established by the late Margaret Anne Cargill of La Jolla, California.

The program focuses on noncommercial concert and field recordings of Appalachian traditional music. Preserving these one-of-a-kind, irreplaceable performances 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 transferring 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. Online access to detailed collection contents and selected audio files is available through Hutchins Library’s Sound Archives Web Page.

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 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. Fortunately, this condition appears to be rare in acetate open reel tape, although it is not unheard of. 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, which is the breakdown of the tape binder by hydrolysis, leading to massive shedding and squealing when playing. These tapes must be restored before playback using a baking technique that is now widely used in the audio industry. Once baked, the tape must be transferred within a week or two before it begins reverting back to the sticky shed condition.

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 professional-level equipment is necessary for preservation work. In the Library’s sound preservation studio which is specially designed for critical listening, open reel tapes and audiocassettes are reproduced using properly calibrated and maintained equipment, including a Studer A807 for open reels and a Tascam 122MkIII for audiocassettes.

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. These procedures include, but are not limited to: visual inspection, slow winding, replacing slotted reels, acid-free paper leaders, proper tape track configuration and playback speed, 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. 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.

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: