Magnetic Tape

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Bigourdan, Jean-Louis, James M. Reilly, Karen Santoro, and Gene Salesin. “The Preservation of Magnetic Tape Collections: A Perspective.” Rochester Institute of Technology: Image Permanence Institute, Rochester, NY, December 2006.

This report delivers information gathered from the field and focuses on the major issues related to preserving magnetic media. It presents research conducted at IPI during the construction of the report. The main objective is to assess current preservation practices by reporting and discussing data based on laboratory testing of magnetic tapes. Conclusions drawn from the research are presented as well as a series of guidelines for preserving magnetic media based on the current situation. The research presented centers on investigating three indicators of tape decay involving the assessment of tape binder condition using three laboratory testing procedures: free acidity, acetone extraction, and friction tests.

Brothers, Peter. “Basic Inspection Techniques to Sample the Condition of Magnetic Tape.” Lodi, NJ: Spec Bros., 2006.

This document describes a 7-point basic physical inspection for magnetic tape.

Brothers, Peter. “Damage Mitigation and Recovery, Magnetic Media.” Washington, DC: National Archives.

“Damage Mitigation and Recovery, Magnetic Media” is written by Peter Brothers of Spec Bros for the National Archives. The advice is in list form and includes steps for initial disaster response, but mostly post-disaster response. There are links to AES, ANSI, and ISO standards. These standards are available for purchase.

Cuddihy, Edward F. “Storage, Preservation, and Recovery of Magnetic Recording Tape.” Pasadena, California: Jet Propulsion Laboratory, California Institute of Technology, 1994.

This is a study on the operational problems of layer-to-layer adhesion, stick-slip, and shedding of sticky organic materials that occur in polyester magnetic tape. It discusses binder hydrolysis as the primary chemical aging mechanism of these tapes, resulting from exposure to the ambient environment. The conclusion specifies safe environmental conditions for tape use, long-term archival storage environments for chemical preservation, procedures for recovery of tapes degraded from exposure to water or high humidity.

Sanner, Howard. “Tapes with Sticky Shed Syndrome.” Ampex Virtual Museum, 2009.

Here you will find a listing of tapes that have been reported to exhibit sticky-shed syndrome. The listing compiled from information reported by members of the Ampex Mailing List, representing those members' first-hand experience with their own reels of tape. It is not, however, the product of scientific testing or statistically valid sampling, and it should be taken only as suggestive of the need for further investigation when tape of a listed type is to be played.

Van Bogart, J. “Magnetic Tape Storage and Handling: A Guide for Libraries and Archives.” Washington, DC: National Media Laboratory and Council on Library and Information Resources, 1995.

This report is a joint project of the Commission on Preservation and Access and the National Media Laboratory (NML), developed within the Commission's Preservation Science Research initiative. It helps clarify long-term storage requirements for magnetic media. The information stems from the industry's accumulated knowledge base, plus media stability studies and operations support activities conducted by the NML for the U.S. Government advanced data recording community. The report focuses on how to properly store and care for magnetic media to maximize their life expectancies. It includes technical explanations for the rationale behind recommended procedures, written specifically for librarians, historians, records managers, archivists, and others who do not have a significant background in recording technology. Additionally, the report is useful for decision-making and cost-benefit analyses for managers and administrators who have responsibility for the long-term preservation of information stored on magnetic media. The text is broken into five sections and an appendix. Sections are: an introduction to magnetic media, potential problems with magnetic media, preventing information loss: multiple tape copies, life expectancy: how long will magnetic media last, and how can you prevent magnetic tape from degrading prematurely.

US Recording Media, LLC. “Tape Time Chart.” Kresgeville, PA: US Recording Media, 2010.

This PDF file is a tape time chart for open reel tape speeds of 1-7/8 IPS through 30 IPS and tape lengths from 600' through 9200'. Chart includes metric.

General Audio Care

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Brylawski, Sam, et al. Proceedings from the Symposium Sound Savings: Preserving Audio Collections. Association of Research Libraries, 24-26 July 2003.

The symposium Sound Savings: Preserving Audio Collections occurred July 24-26, 2003 at the University of Texas at Austin School of Information and was co-sponsored by the National Recording Preservation Board, Recording Preservation Board, and the Library of Congress. The papers from the proceedings were collected on the Association of Research Libraries website and now available via the Internet Archive Way Back Machine. Papers/Presentations include:

  • Review of Audio Collection Preservation Trends and Challenges by Sam Brylawski (Library of Congress)
  • Pictorial Guide to Sound Recording Media by Sarah Stauderman (Smithsonian Archives)
  • Surveying Sound Recording Collections by Hannah Frost (Stanford University)
  • Risk Reduction Through Preventive Care, Handling, and Storage by Alan Lewis (National Archives and Records Administration)
  • The Save Our Sounds Project by Dr. Michael Taft (Library of Congress)
  • The Case for Audio Preservation by Dr. Karl Miller (UT Austin)
  • Contracting for Services by Alan Lewis (NARA) and Anji Cornette (Cutting Corporation Inc.)
  • The Library of Congress Digital Audio Preservation Prototyping Project by Carl Fleischhauer (Library of Congress)
  • Lyndon Baines Johnson Library and Museum Audio Reformatting Project by Jill Hawkins
  • Archiving the Arhoolie Foundation's Strachwitz Frontera Collection of Mexican and Mexican American Recordings by Tom Diamant (Arhoolie Foundation)
  • Copyright Law and Audio Preservation by Georgia Harper (UT System)

Conservation OnLine, “Audio Preservation.” PARS Recording and Photographic Media Committee of the American Library Association, 2008.

The Conservation OnLine audio section is a compilation of articles and sites on various audio topics. The site is arranged by topic, then by author. It was created by the PARS Recording and Photographic Media Committee of the American Library Association and edited by Hannah Frost of Stanford University. This is a good resource to go through to find classic audio information. There may be a few broken links since the site is not routinely maintained.

Library of Congress. “Cylinder, Disc and Tape Care in a Nutshell.” Washington, DC: Library of Congress, 2009.

“Cylinder, Disc and Tape Care in a Nutshell” consists of six sections: Handling, Storage, Packaging/Containers, Cleaning, Bibliography, and Supply Sources. The site covers general tips for audio and specialized tips for discs, reel-to-reel magnetic tape, cassette based audio and videotape, and cylinders. The cleaning section gives an in-depth look at the Library of Congress cleaning solution preference including the MSDS information for Tergitol. Other cleaning options, such as Disc Doctor, are not mentioned. Each section is basic in nature and easy to read.


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Weiner, Bert I. “Video Tape Formats.” Glendale, CA: Bert I Weiner Associates, 1 June 2011.

This is a list of more than 60 videotape formats dating back to 1956. Some of these formats were suggestions made by some of the visitors to the website.

CDs and DVDs

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Byers, Fred R. “Care and Handling of CDs and DVDs: A Guide for Librarians and Archivists.” Washington, DC: CLIR and NIST, 2003.

This guide is intended for librarians and archivists in government, academia, and industry. The document begins with a printable quick reference guide for care and handling that includes general recommendations for long-term storage. It provides guidance on how to maximize the lifetime of optical discs, by minimizing chances of information loss caused by environmental influences or physical handling. Topics include prevention of premature degradation, prevention of information loss, CD and DVD structure, disc life expectancy, and conditions that affect optical discs. The author makes it clear that his findings are not intended to imply a standard, but rather a consensus of several reliable sources on the care of CDs and DVDs.


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Casey, Mike, Bruce Gordon, et al. “Sound Directions: Best Practices for Audio Preservation.”
Indiana University, Harvard University, 2007.

The Sound Directions Project was made possible by funding from the National Endowment for the Humanities in the U.S. The project produced four key results: the Sound Directions publication of findings and best practices, the development of software and tools for audio preservation, the creation and development of audio preservation systems at Harvard and Indiana University, and the preservation of endangered and valuable recordings. Chapters discuss equipment for preservation transfers, digital files, metadata, storage, preservation packages/interchange, and workflows. Each of these chapters is divided into two major components. First, there are overviews that summarize key concepts for collection managers and curators. A more technical section intended for audio engineers, digital librarians and other technical staff follows this first section. It recommends technical practices and summarizes the research. The appendix provides examples of XML, METS, metadata elements and software from Harvard and Indiana University. Research and development focuses on the preservation of field recordings, but the results apply to all types of audio recordings. Research was further localized to post-analog to digital conversion. Pre-conversion recommendations are touched upon briefly but are by no means as comprehensive as the post-conversion research.

European Broadcasting Union. “BWF – a format for audio data files in broadcasting Version 1.” Geneva, Switzerland: European Broadcasting Union, July 2001.

The Broadcast Wave Format (BWF) is a file format for audio data. It is quickly tacking precedence as a recommended digital file format in the audio preservation field. There is a format 0 of this specification and intro to BWF but only slight changes were made to create version 1. This document breaks down what makes up a BWF file and defines the metadata terms associated with these chunks.

European Broadcasting Union. “Specification of the Broadcast Wave Format A format for audio data files in broadcasting Supplement 1 – MPEG audio.” Geneva, Switzerland: European Broadcasting Union, July 1997.

This supplement to EBU Publication 3285 “BWF – a format for audio data files in broadcasting Version 1,” contains the specification for the use of the BWF to carry MPEG audio signals.

European Broadcasting Union. “Specification of the Broadcast Wave Format A format for audio data files in broadcasting Supplement 2 – Capturing Report.” Geneva, Switzerland: European Broadcasting Union, July 2001.

This Supplement to EBU Technical Publication 3285 “BWF – a format for audio data files in broadcasting Version 1,” contains the specification for the use of the BWF to carry information on the audio material gathered and computed by a capturing workstation (DAW). The BWF file is used as a platform-independent container for the sound signal and all the relevant metadata. The receiving archive server is able to extract the needed information from the file and use it as required (e.g. database entry). This supplement specifies a new chunk to carry the information not already present in a basic BWF file and also specifies how existing chunks in the BWF should be used.

European Broadcasting Union. “Specification of the Broadcast Wave Format A format for audio data files in broadcasting Supplement 3 – Peak Envelope Chunk.” Geneva, Switzerland: European Broadcasting Union, July 2001.

This Supplement to EBU Technical Publication 3285 “BWF – a format for audio data files in broadcasting Version 1,” contains specifications for a new chunk used with BWF files, The chunk contains information about peak audio signal levels obtained by sub-sampling the audio. An audio application can use information from this chunk to normalize a file in real-time, without having to scan the entire file. This will greatly impact exchange of audio files between workstations, it can speed up the opening, display and processing of a file if such data is available before the audio data itself is read.

European Broadcasting Union. “Specification of the Broadcast Wave Format A format for audio data files in broadcasting Supplement 4 ­– Link Chunk.” Geneva, Switzerland: European Broadcasting Union, April 2003.

This Supplement to EBU Technical Publication 3285 “BWF – a format for audio data files in broadcasting Version 1,” contains the specification of the <link> chunk. This chunk allows several "linked-up" BWF files to contain continuous audio data that exceeds the 2 GB capacity of a single BWF file. Includes terminology and chunk element definitions.

European Broadcasting Union. “Specification of the Broadcast Wave Format A format for audio data files in broadcasting Supplement 5 –  axml Chunk.” Geneva, Switzerland: European Broadcasting Union, July 2003.

This Supplement to EBU Technical Publication 3285 “BWF – a format for audio data files in broadcasting Version 1,” contains a standard definition of a type of data container for a BWF file: the <axml> chunk for storing and transferring metadata as XML. Includes terminology, chunk element definitions, and an example of an axml chunk.

European Broadcasting Union. “Specification of the Broadcast Wave Format A format for audio data files in broadcasting Supplement 6 – Dolby Metadata, dbmd chunk.” Geneva, Switzerland: European Broadcasting Union, October 2009.

This Supplement to EBU Technical Publication 3285 “BWF – a format for audio data files in broadcasting Version 1,” contains specifications for a new <dbmd> chunk that allows the BWF to carry information to support audio metadata associated with Dolby technologies, such as Dolby E, Dolby Digital and Dolby Digital Plus.

Fleischhauer, Carl. “Format Considerations in Audio-Visual Preservation Reformatting: Snapshots from the Federal Agencies Digitization Guidelines Initiative.” Information Standards Quarterly vol. 2 issue 2, pag. 34-40, Spring 2010.

This document attempts to give the reader information to help determine what format is right for digitization of audio-visual materials. In addition to discussing the file format as container (.wav, .mov, etc.), we must attend to the encoding of the data within the container, its organization, and its internal description. WAV for audio files in linear pulse code modulation (LPCM) form with a sampling rate of 96 kilohertz and a bit depth of 24 per sample is endorsed. History of WAV and BWAV and WAV’s relationship with TIFF is briefly discussed. BWAV metadata chunks are explored as a tool to relay archival information.

International Association ofSound and Audiovisual Archives Technical Committee. “IASA-TC 03 The Safeguarding of the Audio Heritage: Ethics, Principles and Preservation Strategy.” South Africa: International Association ofSound and Audiovisual Archives, 2006.

The Technical Committee of the International Association of Sound and Audiovisual Archives (IASA) aims to identify problem areas and to propose recommended practices for use by sound and AV archives in today's technical environment. These recommendations are a good balance between the ideal situation and the real world. The document starts with recommended practices for planning a digitization project with background on the obsolescence of formats all the way through to preservation metadata and mass digital storage.

Library of Congress. “Audio-Visual Prototyping Project: Illustrative Example of a Statement of Work.” Washington, DC: Library of Congress, 2010.

A Statement of Work can be a confusing document for anyone attempting to navigate a digitization project for the first time. This example document explains each section of a typical Statement of Work and defines terms that are often used by vendors. Most importantly, the document gives specifications of the recommended digital copies (Section 5) that should result from a digitization project.

Library of Congress, “Capturing Analog Sound for Digital Preservation: Report of a Roundtable Discussion of Best Practices for Transferring Analog Discs and Tapes.” Washington, DC: National Preservation Board, March 2006.

Summary of discussion by expert sound engineers that provides good overview of the various types of original analog sound recordings encountered in historical collections, together with best practices for transferring their content. There is a second roundtable document in process as of 2008. This document will discuss the nuances of producing digital file copies of historical analog recordings. One paper on A-D converters is available at

Disaster Recovery

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AVPReserve. Disaster Response Information & Assistance for Collections Affected by Hurricane Sandy.

AVPreserve has provided a list of resources and contacts that can be conulted in case of disaster. There are resources describing the handling and managing of damaged audiovisual media, along with links to other disaster planning resources.

Brothers, Peter. “Hurricane & Flood Recovery Advice.” Lodi, NJ: Spec Bros., 2006.

This document is a primer on how to handle wet magnetic media. The author starts off by briefly explaining how water affects the condition of magnetic tape. He then moves on to
list actions that archivists or librarians may perform during initial damage control and techniques that are better left to professionals.

Library of Congress. “Emergency Preparedness: Introduction.” Washington, DC: Library of Congress, 2010.

The emergency preparedness site at the Library of Congress has information on preparing for a disaster and recovering from a disaster. There is information on assessing the general value of your collection, risk management resource, and insurance. The recovery section includes three short videos (located on the flood, hurricane, and mudslide links) showing how to quickly clean CDs, audiocassettes, and videocassettes for post-disaster inspection. There are also a few scenarios for disaster drills. They aren’t audio specific but can give you ideas for disaster scenarios and training opportunities for staff.

Library of Congress. “Preserving Treasures After the Disaster.” Washington, DC: Library of Congress, 2008.

This site is similar to the “Cylinder, Disc and Tape Care in a Nutshell” and “Preserving Treasures After the Disaster” but goes into greater detail about contamination, mold, and smoke and soot. These are general, but a good primer to conservation techniques for disasters. There are also general principles for air-drying.

Michigan State University. “Disaster Mitigation Planning Assistance.” East Lansing, MI: Michigan State University.

The main highlight of this site is the sample plans link. This sends you to the disaster plan for the Baltimore Academic Library system and to the Conservation OnLine list of institutional disaster plans. Many links on the latter site are broken but contacting the institution is also an option to view their plan.

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