OT: My daughters binaural pure tone audiometry test, opinions, reproducing it in lab

If I'm down 10db 300Hz to 3kHz is it cheating to put in a 10db amplifier? Mikek

On a sunny day (Thu, 15 Aug 2019 01:14:00 -0500) it happened amdx wrote in :

You mean more gain for say above 3 kHz?

I see it this way (never mind the opinion of whatever) when we get older the skin starts to wrinkle a bit. If wrinkling happens to the ear-drum (the membrane that is connected via 2 bones to the inner ear) then it is like a microphone with a floppy membrane and no high frequency is passed on. You cannot just put up the volume as that will shake things and probably damage the membrane.

The ONLY other way I see to get high frequency is have mechanical contact with the skull (piezo?) and that way via the skull-bone activate the fluid in the inner ear, chances are that part is still not affected so much as the ear drum. (I do not know what he effect of long time high frequency vibrations is on the rest of the brain so... ). It is probably easily tested by holding a small speaker against the skull next to the ear, but have not, oh wait, I did test, long ago, but not everybody is the same.

300-300Hz is fine to understand things, many high-end super-heterodyne ;-) receivers use narrow band IF filters just to get clean signals so...

Personally I normally listen with cheap what is it here these days ? Tecsun earphones, ebay few $, see they are no longer on ebay), and that works great for me, I have a whole collection of sort of model earphones from different manufacturers...

If you are into bass and high frequencies I also have a big Sennheiser HD201 headphone the bass is good, the treble is good.

The many $$$ little shit earphones you can buy are worthless to me. The Tecsuns were 4 $.

Of course I also have the 300W stage amplifier and related speakers for if .. :-)

The point is that this guy said that basically, people do not hear above 9 kHz ! We all know that is wrong. I can do a simple test that shows that I can hear up to about 12.5 kHz max. Can't tell how many dB I am down in-between there and 8 kHz very well but that's OK. Frequency response drops off very sharply typically. I can test others' hearing also. BUT I couldn't easily tell if there was a dead-frequency in the middle of the range somewhere...

But you don't need to be a doctor to know that hearing does NOT stop at 8 kHz

You may see it that way.

For most people the cause is that the stereocilia fall off.

False. The primary cause of age-related deafness is that the stereocilia fall off.

On a sunny day (Thu, 15 Aug 2019 07:59:54 +0100) it happened Tom Gardner wrote in :

Old saying by Panteltje Those who do not want to see are effectively blind.

Old saying: that's the pot calling the kettle black. Old saying: you can lead a horse to water, but you can't make it drink.

More importantly, theories of how things might work are valueless, /unless/ they make enable testable /predictions/ to be made.

So, what are the testable predictions that your theories make, and what are the results of the tests.

On a sunny day (Thu, 15 Aug 2019 08:44:59 +0100) it happened Tom Gardner wrote in :

Good thing as it smells the pollution.

if age effects of the eardrum prevent higher frequencies from reaching the inner ear, then it may well lead to degeneration of the related nerve cells, as those do not get activated,. You see he same in people with paraplegia, the leg muscles and system deteriorate as it is no longer activated.

So cause and effect.

You also see this in people who never think for themselves, their related brain circuits finally die off.

You /really/ think the eardrum is a muscle that is activated by neural signals?

Or no cause and no effect, as in this case.

More importantly, theories of how things might work are valueless, /unless/ they make enable testable /predictions/ to be made.

So, what are the testable predictions that your theories make, and what are the results of the tests.

However, the evidence is very strong that industrial exposure to loud high frequency noise pretty much destroys the stereocilla of the hair cells that should be there to pick up vibrations. The high frequencies die first because they get a lot more wear and tear.

Cochlea implants can sometimes fix the problem - the signal paths are still present it is the sensors that have been ruined by overloading.

There are people who think that every crazy idea that *they* have must be right.

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Regards, 
Martin Brown

This is likely to be because the high-frequency hair cells are the ones closest to the eardrum, so they get battered regardless of frequency.

The cochlea is a remarkable organ. It uses electro-mechanical feedback because some of the hair cells are able to act as motors while others immediately adjacent to them are sensors.

In a healthy ear, it is possible to detect acoustic emissions from suitable input stimuli. For example intermodulation products can be detected with a probe microphone in the ear canal when two frequencies are presented simultaneously. In the time domain it is possible to detect echoes from pulse stimuli. These can sometimes resolve damaged areas of the basilar membrane where there are reflections of a proportion of the travelling wave.

Otoacoustic emissions have been used widely for screening testing of the hearing of infants.

John

On a sunny day (Thu, 15 Aug 2019 09:46:24 +0100) it happened Tom Gardner wrote in :

Dear t0m, you deliberately change what I wrote End om commi-nukations

It is rude to snip /directly relevant/ context, particularly context that highlights your mistake.

Thank you for saving me making a similar response re: "high-frequency hair cells are the ones closest to the eardrum, so they get battered regardless of frequency" ;-)

I know it's 3 months late, that's just the frustration of being away from these usenet postings these past three months. :-(

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Johnny B Good