Is it possible to mask bone-conducted sound with air conduction?

[signalblocking]

Is it possible to mask bone-conducted sound with air conduction?

 

[antcollinet]

I suspect only if the air conducion was much higher volume. Once the vibrations reach your inner ear, it doesn't care how they got there.

 

[signalblocking]

I'm unable to quote you but what if there is a frequency mismatch, according to research most human can only hear up to 20KHz through air conduction but through bone conduction, humans can hear up to 100KHz, what if the bone conducted sound is in ultra sound and the air-conduction can only go up to 20KHz, will it be able to mask the bone conducted sound even if the volume is higher.

 

[antcollinet]

Do you have a reference for that - my understanding is bone conduction is worse for high frequencies

 

[Jim Matthews]

Do you have a reference for that - my understanding is bone conduction is worse for high frequencies

Transcranial attenuation of bone-conducted sound when stimulation is at the mastoid and at the bone conduction hearing aid position - PubMed

The median transcranial attenuation depends on stimulation position and frequency. However, the variability is great, both between individuals and within subjects for adjacent frequencies.

pubmed.ncbi.nlm.nih.gov

Yep. It's one of the reasons these come and go - there's always something missing.

 

[pozz]

I'm unable to quote you but what if there is a frequency mismatch, according to research most human can only hear up to 20KHz through air conduction but through bone conduction, humans can hear up to 100KHz, what if the bone conducted sound is in ultra sound and the air-conduction can only go up to 20KHz, will it be able to mask the bone conducted sound even if the volume is higher.

No, this is wrong. This 100kHz claim is based on a three paragraph article published in 1950: https://www.audiosciencereview.com/forum/index.php?threads/two-old-ess-talks.9216/page-2#post-240851

The author doesn't take IMD generated by the signal generator, transducer or the ears into account.

It's worth noting that all of the findings for hearing over 20kHz are based on subject reports. There is nothing in the neuroscience as far as I know which would support transmission or processing of those frequencies.

 

[pozz]

I suspect only if the air conducion was much higher volume. Once the vibrations reach your inner ear, it doesn't care how they got there.

Just to add to this, bone conduction testing with masking (using noise) is normally done to diagnose the kind of hearing loss a patient suffers. Like if you had a heavy blow to the head damaging the middle ear but leaving the inner ear intact.

Usually, with severe hearing loss (>40dB HL), the masker can be at a reasonable level.

 

[Kal Rubinson]

No, this is wrong. This 100kHz claim is based on a three paragraph article published in 1950: https://www.audiosciencereview.com/forum/index.php?threads/two-old-ess-talks.9216/page-2#post-240851

Agreed and his observations on lateralization are questionable. Unfortunately, it is a flawed experiment and one not subjected to peer review.

 

[signalblocking]

I'm unable to find the exact paper where I read it but this paper here says the same thing: https://www.tinnitusjournal.com/art...-sound-in-the-audiometricultrasonic-range.pdf

It's on page 4(actually 2) in the section titled "VIBRATIONAL CHARACTERISTICS OF THE HUMAN SKULL BEYOND THE AUDIOMETRIC FREQUENCIES".

It references to a different paper.

When will I be able to quote user messages?

 

[antcollinet]

I'm unable to find the exact paper where I read it but this paper here says the same thing: https://www.tinnitusjournal.com/art...-sound-in-the-audiometricultrasonic-range.pdf

It's on page 4(actually 2) in the section titled "VIBRATIONAL CHARACTERISTICS OF THE HUMAN SKULL BEYOND THE AUDIOMETRIC FREQUENCIES".

It references to a different paper.

When will I be able to quote user messages?

Hi

I quoted your post just by hitting the reply button.

The clue there is "beyond audiometric". That is just saying what frequencies the bones of the skull transmit - and how. It does not say that the inner ear is capable of detecting those frequencies. The "hearing by bone conduction extends...." applies to ultrasonics modulated by audio frequencies. Those audio frequencies will still be present in the spectrum of the modulated signal, and may be demodulated as described here - https://patents.google.com/patent/US6631196B1/en - , and it will be that the subject is detecting, not the ultrasonic carrier. The benefit here might be that those ultrasonic carriers could be generated with much smaller transducers.

Just think about it - how would you perceive a tone 2+ octaves above 20KHz? What would it sound like?

 

[signalblocking]

Hi

I quoted your post just by hitting the reply button.

The clue there is "beyond audiometric". That is just saying what frequencies the bones of the skull transmit - and how. It does not say that the inner ear is capable of detecting those frequencies. The "hearing by bone conduction extends...." applies to ultrasonics modulated by audio frequencies. Those audio frequencies will still be present in the spectrum of the modulated signal, and may be demodulated as described here - https://patents.google.com/patent/US6631196B1/en - , and it will be that the subject is detecting, not the ultrasonic carrier. The benefit here might be that those ultrasonic carriers could be generated with much smaller transducers.

Just think about it - how would you perceive a tone 2+ octaves above 20KHz? What would it sound like?

Thanks for this information. How does this work, how are non-linearities of ear able to demodulate the ultrasound into audible range.

 

[antcollinet]

Thanks for this information. How does this work, how are non-linearities of ear able to demodulate the ultrasound into audible range.

Nothing I can add over what is written at the link.