Products and Services



STEP is a computer-controlled system for presentation and subjective evaluation of speech and audio signals that can run on any Windows PC. It was developed by a group of former Bell Laboratory acoustics and signal processing engineers. It is typically used in conjunction with an acoustically controlled listening environment, in which signals are presented via headphones or loudspeakers. The PC on which STEP is run must provide a video screen (e.g. LCD) for the listener to view the STEP control panel, a mouse for the listener to interact with the panel and an audio output card or device to interface to headphones or loudspeaker. Click here to go to the ARL STEP web page.


Patent Expert Witness and Patent Litigation Support

ARL patent services are conducted by Dr. Schuyler Quackenbush, founder and CEO of Audio Research Labs. His technical expertise encompasses signal processing, speech and audio processing, including signal compression, media broadcast and streaming. He is an expert in MPEG, ETSI and 3GPP speech and audio standards.

He has more than 30 years of professional experience in engineering and engineering consulting, including more than 15 years as Member of Technical Staff at Bell Laboratories and AT&T Laboratories. He has authored over 30 technical articles, books, book chapters and conference papers and is a named inventor on 22 patents in the U.S. and one in Canada. He is co-author of the ISO/IEC MPEG Advanced Audio Coding standard, and is currently the Chair of the MPEG Audio subgroup.

Please refer to Dr. Quackenbush’s CV for more detailed information.

Dr. Quackenbush has more than 10 years of experience as an expert witness. He has acted as an expert in more than 17 matters, including

  • As an expert in Petition for Inter Partes Review
  • As an expert on patent non-infringement for defense
  • As an expert on patent infringement for plaintiff

In the course of this work, Dr. Quackenbush has

  • Written 26 expert reports
  • Reviewed computer source code 1 time to identify segments indicating possible infringement
  • Been deposed 12 times
  • Testified 1 time in a jury trial

A detailed list of Dr. Quackenbush’s expert witness work is available on request.

Strategies for Standardization

Dr. Schuyler Quackenbush has extensive experience working in standardization bodies such as ISO/IEC SC29 WG11 (MPEG), 3GPP SA4, SMPTE and SCTE). He can advise clients on how to develop strategies for bringing their technology to standards bodies. This can include developing a strategy for a standardization effort, reviewing documents to be submitted, and representing clients at standardization meetings.

Subjective Quality Evaluation

ARL has more than 20 years of experience in conducting subjective listening tests for evaluating the performance of speech and audio coding or processing technologies. We can administer evaluations using BS.1116MUSHRAComparative, or MOS test methodologies on mono, stereo or 5.1 channel speech or audio content. Presentation can be via either headphones or loudspeakers.