Loudspeakers, Rooms And Their Interactions
The final step in delivering recorded sounds to listeners involves the acoustical interactions of loudspeakers and rooms, and the perceptual behaviour of listeners. These complex factors result in strong variations in sound quality, directional and spatial effects in everything we hear in music and film sound recordings. All of the variations are present during the creative process in music and film studios, and they are present in different forms while listeners appreciate these sounds during the playback of recordings.
In audio, loudspeakers and rooms are dominant factors in our attempts to capture, store and reproduce audio artistry. The directional and spatial limitations of two-channel stereo led to many creative solutions in loudspeakers, room design, and electronic enhancements both in the production and reproduction phases. Multi-channel audio changes many rules, and raises questions about what is optimum in terms of loudspeaker directivity, location and number. More confusion is added because of the different schools of thought pervading the film and music worlds. One thing that is constant throughout all of this is the basic requirement for timbral accuracy - good sound quality. This presentation is a review of some of the science underlying these phenomena.
Dr. Floyd Toole
Floyd E. Toole studied electrical engineering at the University of New Brunswick, receiving a BSc, and at the Imperial College of Science and Technology, University of London, where he received a Ph.D. In 1965 he joined the National Research Council of Canada, where he reached the position of Senior Research Officer in the Acoustics and Signal Processing Group.
In 1991, he joined Harman International Industries, Inc. as Corporate Vice President - Engineering. In this position he works with all Harman International companies, such as JBL, Infinity, Harman/Kardon, Mark Levinson, Revel, Lexicon, AKG, Studer, DOD and Soundcraft. He also directs the Harman Research and Development Group, a central resource for technology development and subjective measurements in support of product design and manufacturing.
Dr. Toole's research focused primarily on the acoustics and psychoacoustics of sound reproduction. Most notably, he established methods for subjective and objective evaluations which have been used to clarify the relationships between technical measurements of loudspeakers and listeners' perceptions. All of this work was directed to improving engineering measurements, objectives for loudspeaker design and production control, and techniques for reducing variability at the loudspeaker/room/listener interface. For a papers on these subjects he received the Audio Engineering Society (AES) Publications Award in 1988 and, with Sean Olive, another in 1990.
Dr. Toole has published numerous papers in the journals of the AES and the Acoustical Society of America, chapters in two audio engineering handbooks, and many articles in consumer audio publications. He is a member of the Acoustical Society of America, and a Fellow and past President of the Audio Engineering Society. In 1996 he was awarded the AES Silver Medal for "significant developments in the subjective and objective evaluation of audio devices".
Presented by Dr. Floyd Toole Harman International Date Tues, 24th April, 2001 Time 7:30 pm Place Ryerson Eaton Lecture Theatre, Rogers Communications Building Address 80 Gould Street, Toronto, ON corner of Gould and Church, one block east of Yonge St (Dundas Subway) Pre-Meeting Dinner 5:30 pm Pre-Meeting "Dutch Treat" dinner 5:30 pm at the Pickle Barrel (corner of Edward and Yonge in the Atrium)
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