Marshall Chasin

Marshall Chasin, AuD, is an audiologist and the Director of Auditory Research at the Musicians’ Clinics of Canada, Adjunct Professor at the University of Toronto (in Linguistics), Associate Professor in the School of Communication Disorders and Sciences at the Western University. He is the author of over 200 articles and 7 books including Musicians and the Prevention of Hearing Loss. Dr. Chasin has been the recipient of many awards over the years including the 2012 Queen Elizabeth II Silver Jubilee Award for service to Canada and the Canada 150 Medal in 2017. He has developed a new TTS app called Temporary Hearing Loss Test app.

Temporary Hearing Loss Test: A Preamble to the App, Part 1

Marshall Chasin

In 1995 Erik Borg and his colleagues published a comprehensive review of a number of studies dealing with noise exposure and its effect on both temporary threshold shift (TTS) and permanent threshold shift (PTS). In short, Borg found no relation between TTS, that typically resolves in 16-18 hours, and PTS other than to conclude that one needs to have some

Frequency Transposition for Music: Revisited

Marshall Chasin

Recently I wrote a blog about why frequency transposition (compression or shifting) should never be used with music. Although the reasoning was quite technical, it was based on the fact that in the higher frequency region, speech mostly has a “continuous spectrum” such as a band of noise or friction, much like what one would see with the consonants [s]

Featured image for “Pourquoi devrions-Nous Nous Sou Cier des Enjeux Internationaux ?”

Pourquoi devrions-Nous Nous Sou Cier des Enjeux Internationaux ?

Marshall Chasin

par Ruth Warick Pourquoi devrions-nous nous soucier des enjeux internationaux ? Lorsque le directeur général national de l’AMEC m’a demandé d’aborder le sujet à la récente conférence de l’AMEC, j’ai été enthousiasmée et effrayée. Enthousiasmée parce que c’était l’occasion de parler des enjeux internationaux, mais également quelque peu nerveuse parce que le titre provocateur laissait entendre que je devais vendre

An Open Letter to Hard of Hearing Musicians

Marshall Chasin

This letter is based on my 35 years of working with hard of hearing musicians at the Musicians’ Clinics of Canada. Over the past few years an assortment of new technologies for hearing aids have become available that will allow hard of hearing audiophiles and musicians to reprogram their hearing aids once they leave the audiologist’s office. While on the

Captain Underpants and the 8 track cassette

Marshall Chasin

The new big craze in kids’ books seems to be Captain Underpants. Actually there is nothing new about Captain Underpants- the first book came out in 1997 and to date there are 20 books and several movie spin-offs. The books, written by Dav Pilkey, are centered in Piqua, Ohio, a small town in western Ohio, not far from Dayton. The

Marine life and environmental noise

Marshall Chasin

I decided to go for a swim into the south pacific off the coast of Guam, and submerged to about 36,000 feet just to listen to how noisy the Mariana Trench is. The Mariana Trench is the deepest part of the ocean and runs roughly in a crest from a north to south direction. The pressure at that depth is

Frequency compression can’t work for music

Marshall Chasin

Frequency compression can be useful for speech but never for music. Simply stated, with music frequency compressed harmonics can be too close together and it will sound discordant, or at least fuzzy. Frequency compression of any form can be quite useful to avoid dead regions in the cochlea for speech but this does not follow for music. The difference is that in damaged

Beats, fuzziness and tonality- revisited…or part 2

Marshall Chasin

In last week’s blog entry , the psycho-acoustics of hearing two tones as “beating”, tonal, or simply as a fuzzy mess, was discussed. In short, if two tones are in excess of 30 Hz apart, then they will sound tonal; if two tones are between 20 and 30 Hz, they will sound fuzzy when played together; and if they are

Système de projection de films soustitrés

Marshall Chasin

Système de projection de films soustitrés captiview de doremi pour spectateurs sourds et malentendants actuellement à l’affiche dans les salles de cinéma Cineplex entertainment par Elizabeth Manley, gestionnaire, trademarks and marketing law Cineplex Entertainment LP L’industrie cinématographique mondiale se lance dans un excitant et formidable changement quant à la façon de présenter des films. Les tirages analogiques (ou films 35

Beats, Fuzziness, and Tonality

Marshall Chasin

Actually, Psycho-acoustics is one of the more fascinating area of audition, and I must admit that I use what I learned in those pre-dawn classes every day of my clinical life. The question arises; assuming that the two notes are in the same or complimentary keys, when do two simultaneous notes sound good together? Or conversely, when do two notes make