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.

Why feedback control should be disabled for music programs – Part I

Marshall Chasin

When all is considered, one can truly say that the real advantage of digital hearing aids is feedback management allowing the hearing aid wearer to achieve more gain before feedback is encountered. There is scant evidence about the benefit of any of the other “advanced features” in hearing aids. And other than feedback management (and perhaps a greater bandwidth) hearing

The benefits of distortion in music (and speech).

Marshall Chasin

Our first knee jerk reaction is that the word “music” and the word “distortion” should not be uttered in the same sentence. Music is good (or at least should be of high fidelity) and distortion is, well,… distortion. But if it weren’t for distortion, music would be thin and boring, and speech would be completely unintelligible. Without distortion, music would

L-NAC and hearing loss prevention from loud music

Marshall Chasin

This week’s blog is written in the form of a one page information article that can be given to our patients, or in public education materials about hearing loss prevention. I would suggest leaving out the first paragraph that talks about the recent retirement of Dr. Donald Henderson and start with the paragraph “All cells have a …” Last week

Jim Marshall: The other Marshall

Marshall Chasin

Jim Marshall, also known as the “Father of Loud” passed away at the beginning of April. You don’t need to be a musician to know that the name Marshall is ubiquitous in the field and is a popular music amplifier and loudspeaker combination. Marshall was born in London, England, on July 29, 1923. As a child he was struck with

the -6/octave microphone: Are we doing a disservice if we don’t use it? Part II

Marshall Chasin

The -6 dB / octave microphone is less sensitive for the lower frequencies of speech and music. And many of the lower frequency components are also the intense ones. The net result is that a lower sound level reaches the analog-to-digital (A/D) converter. The net benefit is that the A/D converter is not as easily over driven. There is less

Should all hearing aids have a -6 dB/octave microphone? Part I

Marshall Chasin

In part I of this blog we will overview the basis behind the use of the -6 dB/octave microphone. In part II we will talk about whether it should not only be used for music, but perhaps for both speech and music. Should the – 6 dB/octave microphone be the standard of care and a broad band microphone be the

Music and the Missing Fundamental

Marshall Chasin

When it comes to music, is an extended low end better? The energy spectrum of speech is from roughly the middle of the piano keyboard to a little higher than the highest note on the right side. The entire left side of the piano keyboard is unknown to speech and questions arise why we even have a left side of

What can “music and hearing aids” teach us about “speech and hearing aids”?

Marshall Chasin

Clearly the most important stimulus that a hearing aid design engineer needs to be concerned about is speech. Understandably music is a secondary concern. There are many similarities between music and speech, so designing something for speech will not actually be that different than a circuit or a software program for music. Both speech and music are wide band spectra

Three myths about music and hearing aids

Marshall Chasin

There are many myths about music and how hearing aids should be fit. This is about three of those myths. As technology gets better so will music fidelity Wider is better More advanced features are better Every single hearing aid design engineer has to come to grips with the similarities and differences between speech and music. Although this has always

Do ER-15 musician earplugs really work?

Marshall Chasin

There was a recent presentation given at the National Hearing Conservation Association (NHCA) conference last month questioning the integrity of the ER-15 uniform attenuator for musicians. The ER-15 custom made earplug has been available since 1988 and provides a much more uniform attenuation (lessening of sound energy) across the frequency region than other types of hearing protectors that have been