Arts & Culture

Loeb Music co-authors issue major report on audio preservation

6 min read

A new best-practices report co-authored by Loeb Music Library staff is drawing national and international attention for its comprehensive and candid approach to the field of audio preservation at both the curatorial and technological levels. “Sound Directions: Best Practices for Audio Preservation” provides solid grounding for institutions pursuing audio preservation, either in-house or in collaboration with an outside vendor. A part of the Sound Directions project undertaken jointly by the Loeb Music Library at Harvard and the Archive of Traditional Music at Indiana University (IU), this 168-page publication presents the results of two years of research and development funded by the National Endowment for the Humanities. This work was carried out by project and permanent staff at both institutions in consultation with an advisory board of experts in audio engineering, audio preservation, and digital libraries.

Audio preservation is vital to the survival of an enormous variety of recordings that are by turns cultural, educational, artistic, and documentary — the range covers everything from birdsong to court-case depositions to poetry readings to academic lectures to musical performances. At Harvard, for instance, work is currently under way to preserve the Milman Parry Collection of Yugoslav Oral Epic Poetry, recordings of 20th century poets reading their own works, a collection of Iranian oral histories, and South Indian classical musical performances by major artists of the mid-20th century.

“In the recent past, audio preservation meant the maintenance of a physical object such as a grooved disc recording or an open-reel tape recording,” says Bruce Gordon, audio engineer in Loeb Music Library’s audio preservation studio and co-author of the Sound Directions report. “Before the original was in danger of deterioration, the curator would direct an audio technician to perform preservation transfers of the original recording onto a new magnetic tape — and each tape was in turn copied before it also was endangered.”

Unfortunately, says Gordon, multigenerational analog transfer accumulates noise and distortion. So, true audio preservation was not practical — if even truly possible — until the development of high-resolution digital audio that allowed technicians to copy items without loss of fidelity or increased noise. More recently, thanks to innovations in electronic data storage and a drop in the cost of large storage systems, true audio preservation is not only possible, but practical and cost-effective.

“As a result,” continues Gordon, “audio preservation has evolved from the simple care of physical objects to a system or program of digitization, storage, and access as well as the retention and care of the original object. The complexity of preservation systems requires the curator to rely upon audio engineers, technicians, and information-systems specialists to attend to the technical details.”

Co-authored by Gordon and Mike Casey, associate director for recording services at IU, the Sound Directions report establishes best practices in many areas where they did not previously exist. This work also explores the testing and use of existing and emerging standards and includes chapters on personnel and equipment for preservation transfer, digital files, metadata, storage, preservation packages and interchange, and audio preservation systems and workflows.

The publication is very detailed about discoveries at both Harvard and Indiana. “Our aim was to offer two real-world examples of preservation programs and systems, and to provide the community with a set of realistic best practices based upon existing or emerging standards and upon our own experience,” says Gordon.

Gordon and Casey designed the report to be as user-friendly as possible, despite its necessarily technical bent. “Each major section contains a general overview aimed at the curator, followed by the best practices for the topics of that section,” explains Gordon. “Rationales are given for those best practices, followed by background material, and then the details of the work for the rabid technologist and the very curious curator. There are appendices for the essential but otherwise unwieldy information.”

For example, best practice No. 1, which calls on curators to use skilled audio engineers and technicians when preserving material, may seem self-evident but is particularly imperative considering the extreme fragility of some recordings. Institutions might be tempted to enlist the help of trained students to perform preservation transfers, but using a professional is simply a wiser choice. “Although students can be trained, they typically do not have intimate knowledge of obsolete playback technologies and might compromise the quality of the transfer of a critically endangered object. The object may only be playable once before it is damaged beyond repair, so the curator must be aware of the true cost of unskilled labor,” explains Gordon.

Best practice No. 6 begins to get into the technical side of things: “Use the Broadcast Wave Format for the preservation of audio.” Gordon explains that this format is easily identifiable, and is playable by the largest number of audio software applications, and can store metadata (data about the audio data) as well as the pure audio data. “We believe Broadcast Wave Files will have the longest useful life until that format itself becomes obsolete. Having all of our data in a single format will facilitate the inevitable migration to the next logical format.”

Along with the report comes a suite of 40 pieces of software, designed at Harvard and overseen by David Ackerman, audio engineer in Loeb Music Library’s audio preservation studio, who wrote approximately a third of the program code. The software enables audio engineers to streamline the preservation process and to remove the likelihood of human error from the mechanical aspects. It will be publicly available to the preservation community and, says Ackerman, it should have the potential to help other institutions solve problems similar to those Harvard and Indiana University have encountered.

“My expectation is that the report is going to reach a lot of organizations, both in the U.S. and internationally,” says Ackerman. “The Library of Congress has called us to talk about the software and to say they want to get hold of it, so the impact is there.” The report is all the more valuable because it takes a candid look at Harvard’s and Indiana’s experiences, reporting on the failures as well as successes. “It would have been easy to write a report like this that whitewashes all the problems that you encounter. There was an effort from both institutions not to do that.”

Only a month after release, the publication has been downloaded nearly 1,200 times and each appendix at least 165 times – and some close to 300 times. The project team has also fielded requests for a print version.