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Audio Kyriakakis

Breakthrough audio signal processing technology makes any place in the room an acoustic ‘sweet spot’

October 06, 2004 —

Gone are the days of vying for the best seat in the house. Breakthrough audio signal processing technology developed in the USC Viterbi School of Engineering’s Integrated Media Systems Center (IMSC) has enlarged that acoustic “sweet spot” and made any seat in the living room just right for optimal listening.    

 Chris Kyriakakis

Associate professor Chris Kyriakakis has introduced a signal processing system called MultEQ that distributes sound evenly across a room and optimizes the listening experience for each person.  The system is featured in a new audio/video receiver from Denon Electronics of Japan.  
“Everyone can hear the same high-quality sound, no matter where they are sitting in the room,” said Kyriakakis, a co-founder of Audyssey Laboratories, Inc., of Los Angeles, a spin-off company of the USC Integrated Media Systems Center.  “The system incorporates a room correction and calibration technology that minimizes the effects of room acoustics for multiple listeners.”
Kyriakakis, who is research area director for sensory interfaces at IMSC , said that an auto set-up function automatically determines how many loudspeakers are connected to the system, whether they are connected in phase, and whether they are satellites or subwoofers.  In addition, MultEQ detects the proper crossover point between the satellite speakers and the subwoofer. It then analyzes and calibrates speaker level size and distance.
MultEQ operates by playing a test signal from each loudspeaker.  An inexpensive calibrated microphone is placed in each seat successively to measure the frequency response variations around the room.  MultEQ then creates a filter that optimizes the response at all locations simultaneously.  According to Kyriakakis, the technology can be used on any sound system, from monaural to multichannel surround sound.  Other manufacturers will be releasing products with MultEQ both for the home and the automobile in the first quarter of 2005.
The system resulted from research in audio signal processing, acoustics and psychoacoustics at IMSC’s Immersive Audio Laboratory and was part of USC graduate student Sunil Bharitkar’s doctoral dissertation.  Bharitkar and Phil Hilmes, a USC Viterbi School master’s degree graduate, are co-founders of Audyssey Laboratories.  The company’s commercial success is a direct result of IMSC’s research culture, which encourages close collaboration with industry, said Isaac Maya, IMSC director of industry and technology transfer programs.
“IMSC research is aligned with industry needs and offers higher potential for commercial success,” Maya said, adding that eight small companies in addition to Audyssey have been spun off from IMSC.  “IMSC has successfully concluded more than 100 licenses and technology transfers, including some major commercial successes, and has a broad spectrum of advanced information technologies available for licensing.”
IMSC is the National Science Foundation’s exclusive engineering research center for multimedia and Internet research.  For more information on IMSC’s industry program, visit http://imsc.usc.edu/industry, or contact Isaac Maya at (213) 740-2592 or by email at imaya@imsc.usc.edu.
--Diane Ainsworth