Resources

Technical Brief – Audio Recordings

The Naropa University Archive Project makes every effort to adhere to best practices for preservation and digitization of audio materials, which includes a commitment to open-source software. The practices we have adopted are outlined in this technical brief.

Preservation of Original Tapes

Most of the original tapes are magnetic analog audio cassettes, ranging in age up to 30 years. The lifespan of an audio cassette, stored under proper conditions, is estimated to be about twenty years. Thus, many of our tapes have exceeded their natural life.

The original unprocessed audio cassettes are currently stored upright in metal tape cabinets in the Special Collections room in the Allen Ginsberg Library.

If we encounter technical problems with a tape, to restore them we contract with Airshow Mastering, a nationally recognized professional audio restoration and mastering studio in Boulder (www.airshowmastering.com). Our most common problem is print-through caused by a tape being stored for a long period in a tight wind.

After completion of the digital transfer, to extend the life-span of the original tapes as long as possible, they are placed in off-site climate-controlled storage at Iron Mountain’s Denver facility. 

Transfer to Digital Media

Original cassette tapes are transferred to a variety of digital media that serve as preservation or access copies.

The digital transfer is conducted on an iMac computer system using Digidesign ProTools audio software. The tapes are recorded into the system using an adjustable high-end Nakamichi Dragon cassette player. The analog audio signal passes through a DigiDesign 002 audio processor and a Lucid AD9624 analog/digital converter to create the digital audio file. Levels are set to capture a flat audio signal with as much detail as possible.

The flat audio signal is captured as a preservation master in real-time at 44.1khz in a 24-bit broadcast WAV file (BWF). These unaltered files are written to a 2.5 terrabyte RAID storage system running on a Macintosh XServe server, housed in a secured climate-controlled machine room at Airshow Mastering. The files are also written to 1 terrabyte LaCie hard drives, housed in our Naropa studio, and to Sony AIT magnetic data tapes, stored at Iron Mountain in Denver. All of these copies are treated as redundant preservation masters.

Listening copies are created as 16-bit WAV files. Audio technicians process the audio files to remove silent gaps in the recordings, normalize gain, and execute noise reduction using the WAVES X-Noise plug-in for ProTools. The “sweetened” WAV files are written to CDs for use in CD players in the classroom. They are also backed up on the XServe RAID system, followed by delivery to the Internet Archive for online access (www.archive.org). The Internet Archive performs further conversions on the WAV files, offering them online in five formats, both streaming and downloadable. Finally, MP3 files are created and loaded into an iMac listening station in the Allen Ginsberg Library, for on-site use by students, faculty and visiting scholars.

Metadata Collection and Cataloging

During the real-time transfer audio technicians log a variety of metadata. They record technical data related to the original tapes and also create complete content notes about the subject matter included on the tapes. After the entire process is completed the audio techs log technical information related to the preservation and listening copy media.

The metadata is recorded in an administrative database. This is a custom-written passworded SQL database running on the Macintosh XServe co-located at Airshow Mastering.

Catalogers in the Allen Ginsberg Library access information from the administrative database to create Library of Congress compatible MARC21 records. After completion these records are distributed to OCLC/WorldCat, for use by scholars and researchers in libraries worldwide. The records are also crosswalked to a Dublin Core format for delivery to the Colorado Digitization Program’s online database, where they are OAI harvestable.

For More Information or to Contact Us

To listen to the audio online, visit the Internet Archive at www.archive.org and click on “Education.”

For more information about the holdings of the Jack Kerouac School of Disembodied Poetics Audio Collection, visit our web site at www.naropaarchive.org

For more complete technical information, or to arrange a visit, contact Karen Cuiskelly, Archivist, at kcuiskelly@naropa.edu