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Handsfree intra oral electronic bluetooth larynx

Published: 01 November 2017
Last updated: 05 January 2023

The electrolarynx is the most widely used device for speaking without vocal cords. However, its use is not very elegant, therefore I built a prototype of an electronic bluetooth larynx. The electronic larynx can improve the life of laryngectomy patients. 

Operation of the electronic larynx

The electronic larynx is a miniature speaker, invisible hidden in the mouth, that produce the sound that is normally produced by the vocal cords. In this way, a person can speak by articulating as usual without producing a sound themselves.
The electronic larynx is put between the lower premolars and the cheek. The advantage is that there is much space and the speech is not hindered by the device.

Handsfree intra oral electronic bluetooth larynxHandsfree intra oral electronic bluetooth larynx

This video shows a simulation of the electronic larynx when it is used used with pitch control and vowel control:

Unfortunately, I've had very little time to make decent demonstration videos. The problem is that there is no remote control yet, so I had to pre-record the sound and then, as it were, post-sync.

The electronic larynx contains a small phone speaker, amplifier, bluetooth module and a battery. In my simple prototype, the sound is coming from the smartphone, where it is stored, and than sent to the electronic larynx via bluetooth. 

There was a patent on an identical device granted in 1994, which has now expired: However, this patent has not been exploited. The patent describes the operation of the electronic larynx in detail.

Intra oral electronic bluetooth larynxIntra oral electronic bluetooth larynxIntra oral electronic bluetooth larynxIntra oral electronic bluetooth larynx

Electronic bluetooth larynx circuit

Intra oral electronic bluetooth larynx circuitIntra oral electronic bluetooth larynx circuit

Intra oral electronic bluetooth larynx PCBIntra oral electronic bluetooth larynx PCB


Panasonic EVQ P6DB35 tactile switchPanasonic EVQ P6DB35 tactile switch

The Iphone SE speaker is reduced in size and the hole that arises is sealed with 5 min epoxy glue. 
Note other glue can damage the interior of the speaker due to vapor.

Iphone SE speakerIphone SE speaker

An waterproof ear mesh is glued to the Iphone SE speaker with epoxy.

Ear meshEar mesh

The advantages

  • The voice of the patient before the laryngectomy can be recorded so that the voice is retained.
  • The articulating is greatly simplified if you can choose a number of vowels, instead of, for example, just the aaa.
  • By using a wireless remote control that allows you to control the vowels and pitch, the speech sounds very natural.

Remote control

I don't have time to develop the remote control. Here's an impression of what the remote control might look like. The idea is that you can control 4 vowels and the pitch with the fingers of one hand. The pitch is controlled by the force by which the vowel button is pressed.

Remote controlRemote control


I only made a simple prototype, many improvements are possible, for example:

  • Take a larger battery
  • Take a loudspeaker with more volume
  • Making water proof by using wireless charging
  • Making water proof by using auto power-on
  • Prevent the speaker from being blocked by the cheek

Who is interested?

I am looking for a university or company that could take this up. I have no commercial interests. 

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