Wayne's World

H. Christopher Schweitzer, Ph.D. Dr. Schweitzer is Director, HEAR4-U International and Technical Consultant for IMH Corporation.   In a previous post, Dr. Schweitzer discussed accuracy and reliability of hearing threshold measurements, describing the inaccuracies and problems that exist with current methods.  That hearing aids are fitted based on poor baseline information has led to the introduction of other tests and

by Christopher Schweitzer, Ph.D.   H. Christopher Schweitzer, PhD has a long history of research, development, and clinical activity related to hearing and hearing aids, and continues to own the Family Hearing Centers of Colorado. He is a frequent contributor to HHTM (Hearing Health and Technology Matters).   Background Students in Signals and Systems learn that there’s an important difference

In a previous article, in discussing hearing aid power supplies, it was mentioned that depending on its design, a power supply (battery) may obtain its energy from different types of energy sources, including electrical energy transmission systems, energy storage devices such as batteries, and fuel cells.   Hearing aids have used storage batteries for many years, but what about hearing

Hearing aids are electronic devices that apply amplification provided by a power supply, most usually called the “battery.”  The power supply provides the energy to drive the hearing aid (an electrical load).  What the power supply (hearing aid battery) does is to essentially convert one form of electrical energy to another.    Battery Basics for Hearing Aids Although historically, “battery”

I wish all a Merry Christmas, Happy Hanukkah, and an enjoyable New Year. That aside, what does this holiday season have to do with earwax? Nothing that I am aware of.  However, it is that time of the year when we take one of our most read posts for 2016 and share it again with all of you.  And for some reason,

Research related to the occlusion effect (OE) suggests that the OE is minimized when contact of the ear insert (closed coupled in this case) is made with the bony ear canal1,2.  Measurements of the OE for various in-canal devices are numerous and essentially support this conclusion.  But, to what extent does the cartilaginous/bony ear canal junction impact the occlusion effect?

A number of years ago, an article was published describing the importance of the impedance formula in interpretation of audiograms1.  The article by Campbell offered a fairly simple and visible way to help understand the audiogram, based on stiffness and mass, and the impact of these two elements on conductive hearing loss.  It is recognized that today more sophisticated methods

The answer is yes – there is an upper limit to sound.  But this depends on how sound is identified and this article relates to sound in air. Sound in Air Sound is a series of longitudinal waves travelling in air caused by oscillations of pressure in the air (Figure 1).  Sound consists of a pressure wave, having regions of

How loud can sound get?  Could loud sound kill you?  Are there limits, and if so, what are they?  How are such things determined?  All of these are interesting questions and an attempt will be made to answer these as best possible. Two important lessons are supported by this article: one, the loudest thing in the world does not have

A previous post described the Doppler effect in a simplified manner as it relates to movement and sound waves.  This post expands on this somewhat by providing a series of Doppler effect animated images to clarify the role of a moving object and its impact on the sound.  It has been said that a picture is worth a thousand words.