Technical analysis and comparisons and Information about Tomatis Effect method, Listening training sound therapy Machines, Tomatis-based Machines by Valerie Dejean, student of Tomatis 1991 and 1997.

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There are other things to consider besides the features on the EE that produce the “Tomatis Effect”.

Input-What we listen to - Music and Voice


We need to consider the input, or what is transmitted to the   makes it work.  In the early days the main input to the EE was the human voice.  A singer would sing into a microphone that was filtered and gated through the EE.  Later as Tomatis worked with developmental and learning disabilities the clients either couldn’t talk or their voices were not of sufficient quality to make the machine gate. Therefore Tomatis needed another source of input to re-educate the ear. 


Tomatis came from a classical music background and he searched extensively for music that had the correct harmonics to make the EE gate in a manner consistent with a good voice.  He found some of the music of Mozart most compatible.  Not all Mozart, but specific pieces that resemble the human voice most approximately.  He started to use this music to train the listener in the high frequency ranges of fetal listening.  The choice of music is what allows the machine to gate even when fully filtered without having to play the music loud.


Please note that Tomatis did not use Mozart to deliver the Mozart Effect. Tomatis used the music, frequently Mozart, that best allow the EE to deliver the “Tomatis Effect”. In this way the Tomatis Method is more of a “sound” therapy than a“music” therapy.

Valerie Dejean with Tomatis
Human voice and particularly one’s own voice is critical to closing the loop of listening in the process of reeducating the ear as was described in detail when discussing the microphone.  Other human voices that are used in the Tomatis Method are pre-recorded input that allows the client to repeat certain single words and sentences. These repeat texts allow for practic eof words that are rich in high frequencies or sibilants. Often repeat texts are filtered to encourage listening in increasingly higher frequency ranges. Others are designed to hear differences in similar sound such as “f” and “th”.  All of the inputs (music and voice) are modified though all the other features of the EE. microphone work

Monaural vs. Stereo Sound

There are very sound reasons for the Tomatis Method being delivered through monaural sound even if it doesn’t sound as symphonic as stereo sound.  All of Tomatis’ early research was into what distinguished a good listener from a bad one and he determined quite early that the two ears have different roles in listening. The right ear heard higher frequency sounds better than the left ear and the right ear had faster neurological pathways to the left hemisphere of the brain, the side of the brain we use to understand language as well as to organize our speech. The right ear also has a faster pathway to the voice box.  The reason that the Tomatis sound is monaural is that this is easier for the brain to process since both ears are listening to the same thing versus stereo where the sound is different in each ear. This is, after all, therapy! Developmentally it is very important to train the ear in the easiest form of processing before moving to more advanced levels of processing stereo sound. In the Tomatis Method of re-educating the ear to listen better we start with monaural sound of equal volume and gradually encourage the right ear to gain control of the listening function.

Stereo presentation of music is often touted as an improvement of the Tomatis Method. However stereo (vs.monaural) sound creates complications in delivering the Tomatis Effect.Since the music drives the gate, the fact that each ear is hearing something different in a stereo presentation also means that each ear perceives the gate at different intervals.


This doesn’t make sense as a treatment neurologically. The goal of the gate is to train the ear (or more accurately, the auditory system) to pay attention. The Gating, the Delay, the Bone and the Air Conduction, are all programmed together to facilitate paying attention. This is complicated enough for the client’s auditory system and for the therapist’s programming efforts. With Stereo, you have made the system exponentially more complicated and the odds are that you will have created a distraction, rather than an improvement, in the client’s listening. And furthermore, giving some due respect to the man who’s created the method, stereo delivery is not at all consistent with Tomatis’ theories. Tomatis was very knowledgeable about stereo and knew it was not possible to incorporate it within the Tomatis Method delivery system. 

Secondly it is not possible to have the delay between bone and air conduction when music is delivered in stereo, As discussed earlier, this delay function is a very important feature of the electronic ear as it allows the person to prepare for incoming sound.

Lengthof theProgram:

Tomatis experimented for thirty years on how best to deliver his program.  There were many variations from people listening six-eight hours a day to people listening a couple of times a week for up to a year.  He eventually came to the standard of listening for sixty hours over thirty days, done in a three-month time span.In order to change neurological encoding, the re-education of the ear needs to be delivered intensely for a sustained amount of time. It takes one to one and a half hours to get the brain to change how it is listening.  During the last   to forty-five minutes the brain is using the new listening.  The next day the brain goes back to its old habit and we need to re awaken it.  We do this every day for ten to fifteen days and now a new habit of listening has been established.  We now have a four to six week break to allow the client to use his “new ear” before we induce new changes.  Two more eight to ten-day intensives are done over the next two months and specific to the individuals pace, the next development stages are induced. This is the standard program for a determined listening disorder. Programs for enhancement, foreign language acquisition, accent reduction, and musicians can be accomplished in less time.


Valerie Dejean