Institute for Telecommunication Sciences / Research / Quality of Experience / Audio Quality Research / Public Safety Audio Quality / Audio Source Files
Audio Source Files
Talker and Background Noise Source Files
Following are clean, high-quality, talker-only and background noise-only audio files. These files were used to mix talker audio with background noise audio to create the files for the MRT experiments reported in 2008, 2010,* and 2012. Click on Test Audio & Results to download the files that combine talker and background noise audio passed through public safety communications systems, as well as the listener results data collected for each experiment.
*This report was readied in 2010 and moving through channels for a different publishing outlet. It was published as a National Telecommunications and Information Administration Report in 2013.
Atkinson, D. and A. Catellier, “Intelligibility of Analog FM and Updated P25 Radio Systems in the Presence of Fireground Noise: Test Plan and Results,” NTIA Technical Report TR-13-495, May 2013.
You can use the MRT audio files provided here with the ITS-developed software tool for objective estimation of speech intelligibility (technical paper here). The software tool, called ABC-MRT (available here), reduces the time and expense usually associated with MRT experiments to gauge speech intelligibility.
Downloading and Using Compressed Files
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A table of files displays.
In the file table, click the name of a compressed file to download it.
File sizes can be 2GB or more, so be patient.
Some compressed files might include several subfolders and over 1,000 files. Take care to review the readme.txt files, which provide important information concerning the files contained within a given folder. Audio files are WAV format. Results data from our 2008, 2010,* and 2012 MRT experiments is provided in csv, mat, and xls format.
*This report was readied in 2010 and moving through channels for a different publishing outlet. It was published as a National Telecommunications and Information Administration Report in 2013.
Atkinson, D. and A. Catellier, “Intelligibility of Analog FM and Updated P25 Radio Systems in the Presence of Fireground Noise: Test Plan and Results,” NTIA Technical Report TR-13-495, May 2013.
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NIST/CTL and NTIA/ITS (The PSCR program, or “PSCR”) hereby grants permission for you (or your organization) to use the Modified Rhyme Test Audio Library (“MRT Library”) and any audio files or other content posted thereon (“Library Content”), solely for internal research and development purposes to process and assess audio quality. You will not use, copy, reproduce, distribute, modify, prepare derivative works, transmit, broadcast, display, sell, license or otherwise exploit the Library Content for any other purpose whatsoever. You shall not distribute any Library Content to any third party. You agree to destroy any and all copies of Library Content, if any are made, upon conclusion of the relevant audio processing and/or testing.
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