Can't find my old entry on this in HB!

SilenTalk works by inducing an ultrasonic sound (voice) in your larynx. (see links)

A bluetooth mic picks up the sounds, translates them to a digital stream of audio, which, when reaching your smartphone, is interpreted as regular voice, and sent to your ears as well as to the other person listening to you.

See link: with trutone you can talk normally. With SilenTalk you can talk silently.

Only you and your listener can hear you.

Talk in the movie theater, talk at an important meeting. Talk at night without waking anybody up.

Its an unheard-of invention helping free speech!
-- pashute, Nov 09 2011

TruTone - similar device, but one that anyone can hear http://www.youtube....watch?v=AYydnhu6NbU
The SilenTalk creates a sound that you can hear only with the SilenTalk Listener program in your smart phone [pashute, Nov 09 2011]

(??) Wow! this is a genius invention http://current.com/...aper-thin-walls.htm
Much simpler and better than mine. Why didn't I think of it! [pashute, Nov 22 2011]

The throat microphone Throat microphone
a competing idea [pashute, Nov 22 2011]

Mutemic https://newatlas.co...e-microphone/14766/
Silent karaoke mic link is dead so I put this one up instead [pashute, Jun 15 2021]

//hypersonic// Do you mean ultrasonic? If so, it won't work; it's all to do with formants. If not, what do you mean?

Subsonic (too quiet to hear, but detected by sensitive microphones) FTW; but that's baked by throat microphones and training, without a synthesized tone.
-- spidermother, Nov 09 2011


Ultrasonic at the barely audible level works. Tested and all, by yours truly, in an audio lab. Sorry for the mistake in wording, thanks for the remark. Corrected.
-- pashute, Nov 14 2011


Easier would be to speak through a microphone and speaker that in the process adds noise such as a popular song for example. The reciever would pick up your transmission through a mic and remove the song leaving your spoken message played through an earpiece.
-- rcarty, Nov 14 2011


I agree with [spidermother,] I think you mean subsonic.

A few questions:

1) How do you pick up sibilants, fricatives, plosives and other unvoiced phonemes? These do not rely on glottal pulses for excitation.

2)Where is the laryngeal excitation source located?

3) Where is the bluetooth mic located?

4) How is it to be powered?
-- csea, Nov 14 2011


(Subsonic appears to be used only for "slower than the speed of sound", not "too quiet to hear"; my bad.)

I would still like you to spell out what you mean: is the sound induced in the larynx inaudible without SilenTalk because of

(a) high frequency,

(b) low amplitude,

(c) both (a) and (b)

(d) something else?
-- spidermother, Nov 14 2011


Spider: (a) only. High frequency.

Not subsonic. It works more like the artificial larynx, except that it emits an ultrasonic tone. The frequency can be changed by your button similar to the trutone (see link) but all are ultrasonic frequencies, slightly above the audible range.

[csea] 1) The ultrasonic high frequency inaudible to human ear tone enters the throat just like the tone from the artificial larynx does: Its a mixture of your breathing air out, and the resonating larynx. - But in this case its resonating very fast in what becomes inaudible.

The shape of your mouth, location of your tongue and teeth etc are all part of what makes up the the voiced as well as unvoiced phonemes. The closing of lips teeth and tongue create the plosives, fricatives and sibilants.

A regular artificial larynx is easy to use and does not take much practice. This would be the same, except that without the bluetooth mic and processor you would hear only whispers (and those could be lowered to a level that they become unheard at all), and perhaps smacking of lips.

2) So the laryngeal excitation is taking place in the larynx, by the larynx, or echoed off the larynx area, in a similar way to what happens with a conventional artificial larynx.

In important part of speech is the tones, and a Trutone like device will solve that.

3) The bluetooth mic (and processor) is located outside the mouth, or on the input side of the phone, so the talking person could put it to their mouth. It transforms the ultrasonic sound into audible sound.

4) By batteries. Just like an artificial larynx is powered by batteries, and just like a bluetooth earphone works on batteries.

A passive sensitive ultrasonic receiving mic could lower the power needs, and this in turn would make for a smaller device, perhaps even connected to a smartphone directly, for its battery power.

-----

About subsonic implementations: When I first conceived this idea and tried to raise money for it around 2000 or 2001, (and even submitted a provisional now expired) I researched and found a company that makes what you described - a mic on the throat, for the military so they can communicate silently. But this idea is for civil use.
-- pashute, Nov 22 2011


The throat microphone idea has been deleted and in wayback machine is missing already in 2003 with no prior record.

If you had the idea, could you at least tell me what it was?
-- pashute, Jun 15 2021


"infra-"
-- FlyingToaster, Jun 15 2021


<imagines two people, one each end of the fouth's Doctor's scarf/>

One of the, being developed, EEG headsets plus phone hardware will probably be the quietest.
-- wjt, Jun 20 2021



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