CDP
Digital Audio Working Group
Digital Audio Best
Practices
Version 2.0
November 2005

1. Introduction
1.1. Purpose and Scope
1.2. Recommendations Strategy
1.3. Updating the Colorado Digitization Program Digital
Audio Best Practices
1.4. Acknowledgments
1.5. Supporting Documents
Questions to Ask Before Beginning an Audio Digitizing Project
Legal, Copyright and Intellectual Property Issues for an Audio
Digitizing Project, with Sample Release Forms
CDP Dublin Core Metadata Best Practices, Version 2.1
Guidelines for Outsourcing Audio Reformatting
2. Understanding Audio
2.1. A Brief Overview
2.2. Additional Considerations
3. Planning and Implementing an Audio Digitizing
Project
4. Legal, Copyright, and Intellectual Property Issues
5. Metadata for Digital Audio
5.1. Audio Metadata Standards
5.2. Audio Metadata in Dublin Core
5.2.1. Format
5.2.2. Digitization Specifications
5.3. CDP Dublin Core Metadata Best Practices
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6. Guidelines for Creating Digital Audio
6.1. History of Audio Recording Devices
6.2. Modes of Capture
6.3. Sample Rate
6.4. Bit Depth
6.5. Source Types
6.6. File Types
6.7. Digital Audio Toolbox
6.8. Born Digital Recording
7. Outsourcing Audio Reformatting
8. Quality Control
9. Storage and Preservation of Digital Audio
10. Delivery of Digital Audio
10.1. On-site Delivery
10.2. Online Delivery
10.3. Podcasting
11. Digital Audio Glossary
12. Digital Audio Resource List
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1. Introduction
Prepared by the CDP Digital Audio Working Group
Carson Block, High Plains Regional Library System, Fort Collins
Joe Conway, Naropa University Archives, Boulder
Lance Christensen, Colorado State Archives, Denver
Leigh A. Grinstead, CDP Projects Coordinator, University of Denver
Wendy Hall, Carnegie Branch Library for Local History, Boulder Public Library
John Hansen, University of Texas, Dallas
Tim Hawkins, Chair, Naropa University Archives, Boulder
Jill M. Koelling, CDP Executive Director, University of Denver
Holley Long, University of Colorado, Boulder
Tami Morse-McGill, Colorado State University, Fort Collins
Mark Shelstad, University of Wyoming, Laramie
1.1. Purpose and Scope
The transfer of original recordings to digital formats is a process that helps
protect the original analog recordings from unnecessary handling, can serve as a
preservation process, and can provide access that might otherwise be
unavailable. These digital duplicates may be copied without noticeable signal
loss and safely accessed without concerns about the destruction of original
material. This transfer process, when handled properly, can prove to be both
easy and cost effective for most historic collections. As the technology continues
to improve, this alternative will become even easier and more cost effective,
helping to preserve and make accessible the historic audio collections of
museums, libraries, and archives.
The purpose of this document is to provide guidelines and a set of best practices
for cultural heritage institutions interested in converting analog audio recordings
to digital formats. Recording audio directly into digital formats is also addressed.
There are many historic audio collections in museums, libraries, and archives
that may be in poor condition and are becoming increasingly fragile due to their
age or storage history. We hope this information will help to preserve these
collections and make them more widely accessible.
If you are unfamiliar with audio terminology, or the terminology related to digital
media, please refer to section 11 for a glossary of terms. We recommend that
you familiarize yourself with these terms before continuing.
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1.2. Recommendations Strategy
Taking into consideration all of the items discussed in this document, our goal is
not to provide absolute recommendations, but rather to provide guidelines for
making informed decisions about best practices for particular projects. We offer a
tiered approached to best practices that takes into consideration the nature and
quality of the audio source material, the intended use of the resulting digital audio
files, and the nature and available resources of the institution conducting the
project
1.3. Updating the Colorado Digitization Program Digital Audio
Best Practices
In the fall of 2004, the Collaborative Digitization Progr am (CDP), formerly known
as the Colorado Digitization Program, received funding from the Institute for
Museum and Library Services (IMLS) to create an infrastructure for the delivery