Fletcher Munson curves vs own ears

[audio_file]

Seeing that hearing damage, age, and other factors can change our ears' tonal balance and thus audio perception, it makes sense to me that our own curves would be slightly different to the Fletcher Munson ones and to each others ones.

This site has a way to test our own curves roughly. http://newt.phys.unsw.edu.au/jw/hearing.html

Maybe we could compare what we get, or even link a different test page if you know of one.

 

This is my result:

Edited January 2, 2020 by audio_file

[audio_file]

This is at a lower level:

[Ihearmusic]

 

There you go. Industrial hearing loss in one ear might sway the result a bit.

[Al.M]

The FM curves were apparently based on 18-25 year olds so older people and with hearing loss are obviously going to be a little different. From about age 40 years the higher freq (12khz and above) start to fall dramatically. Most music content doesn’t have much more than 10khz info so most healthy hearing for age below say 70 years should still be good to enjoy listening to music.

 

Most of your test results above roughly seem to follow the FM curves.

Edited December 31, 2019 by Al.M

[audio_file]

The first two I did with my Sennheiser Momentum 2 over ear headphones, now I tried it with my AKG K550 ones and got this:

The bass response of the two clearly differs.

[Al.M]

Probably due to different headphone acoustics, varying background noise conditions and the test not being very accurate to start with.

[audio_file]

14 minutes ago, Al.M said:

Probably due to different headphone acoustics, varying background noise conditions and the test not being very accurate to start with.

There wasn't much background noise and my headphones block out a lot.

The two headphones do sound different though and have a different tonal balance.

This test is not meant to be accurate and is linked here for fun.

[Pim]

Everybody seems to have the same shape curve. Mine seems to be more pronounced. I wonder whether that's got something to do with the use of Bluetooth headphones (B&W PX)

[Al.M]

5 hours ago, Pim said:

Everybody seems to have the same shape curve. Mine seems to be more pronounced. I wonder whether that's got something to do with the use of Bluetooth headphones (B&W PX)

You can get a free audiology test and advice at many centres, just google for one near you. 

 

 

[stereo coffee]

On 01/01/2020 at 2:51 AM, Al.M said:

The FM curves were apparently based on 18-25 year olds so older people and with hearing loss are obviously going to be a little different. From about age 40 years the higher freq (12khz and above) start to fall dramatically. Most music content doesn’t have much more than 10khz info so most healthy hearing for age below say 70 years should still be good to enjoy listening to music.

 

Most of your test results above roughly seem to follow the FM curves.

I recall writing about this  before, so is any chance of reading both of these articles please.    There is musical frequency content out to 102.4 khz   http://www.cco.caltech.edu/~boyk/spectra/spectra.htm

 

We humans have perception of frequencies above 20khz detailed here:    http://wilson-benesch.com/reviews/Life_Beyond_20kHz_Blackmer_SVC_Sep-1998.pdf    Basically put we absolutely need audio equipment to have ability with frequency to at least  50khz,  because if we change those frequencies which we perceive with filters, it changes the frequencies we directly hear. 

 

 

 

[sir sanders zingmore]

19 minutes ago, stereo coffee said:

http://www.cco.caltech.edu/~boyk/spectra/spectra.htm

From the link. Says it all really : Author's Notes, May 4, 2000 
At the request of people involved in standards-setting for audio, who wanted this information made available as soon as possible, I published this original paper here, rather than in a professional journal

 

20 minutes ago, stereo coffee said:

We humans have perception of frequencies above 20khz detailed here:    http://wilson-benesch.com/reviews/Life_Beyond_20kHz_Blackmer_SVC_Sep-1998.pdf   

This author simply asserts that he can hear the effect of stuff above 20khz and then goes on a big hand wavy talk to justify it (or perhaps it’s just an advert for earthworks mics, hard to tell). 

[Ittaku]

40 minutes ago, sir sanders zingmore said:

This author simply asserts that he can hear the effect of stuff above 20khz and then goes on a big hand wavy talk to justify it (or perhaps it’s just an advert for earthworks mics, hard to tell). 

Yep, every single "above 20kHz" study has been debunked and not been reproducible. The Japanese one was the last famous one to get notoriety. Was still bad science.

Edited July 20, 2020 by Ittaku

[Al.M]

1 hour ago, stereo coffee said:

I recall writing about this  before, so is any chance of reading both of these articles please.    There is musical frequency content out to 102.4 khz   http://www.cco.caltech.edu/~boyk/spectra/spectra.htm

 

We humans have perception of frequencies above 20khz detailed here:    http://wilson-benesch.com/reviews/Life_Beyond_20kHz_Blackmer_SVC_Sep-1998.pdf    Basically put we absolutely need audio equipment to have ability with frequency to at least  50khz,  because if we change those frequencies which we perceive with filters, it changes the frequencies we directly hear. 

 

 

 

Yes, I read those links previously and it isn’t conclusive. The articles are quite old 1998 and 2000, sporadic and not replicated in other science studies and literature on the subject as a whole. The mechanism of perceiving the higher frequency sounds is speculative, describing it as possibly via bone structures of the ear (how does 50 kHz or 100khz vibrate an ear bone structure?) and not the inner ear hair cell receptors where in middle aged people we severely loose that ability through normal age induced hearing loss down from 20khz age 10-25 years to 12-14khz age 40-50 years.

[Pim]

1 hour ago, stereo coffee said:

    Basically put we absolutely need audio equipment to have ability with frequency to at least  50khz,  because if we change those frequencies which we perceive with filters, it changes the frequencies we directly hear. 

 

 

 

What happens if you just leave those frequencies out? Nothing changed, nothing lost right?

[Ittaku]

1 minute ago, Pim said:

What happens if you just leave those frequencies out? Nothing changed, nothing lost right?

That's correct. There are some scans of the brain done suggesting we respond to ultrasonic frequencies even if we can't tell whether they're there or not in blind testing, suggesting they have a "feel good" phenomenon associated with longer term listening that wouldn't be there without them, but that science has not been validated.

[sir sanders zingmore]

16 minutes ago, Ittaku said:

Yep, every single "above 20kHz" study has been debunked and not been reproducible. The Japanese one was the last famous one to get notoriety. Was still bad science.

It seems limits on audible frequencies are exceeded by the frequency with which these articles get trotted out. 

[Pim]

Getting this back on topic. I thought about maybe doing this test on my speakers and then using the equaliser in Roon to adjust so that the frequency spectrum sounds flat with my system in my room listening to it with my ears. Should be interesting. Possibly not very scientific.

[stereo coffee]

3 minutes ago, Pim said:

What happens if you just leave those frequencies out? Nothing changed, nothing lost right?

You would then be altering by blocking  the higher register natural frequencies musical instruments are capable of. The better approach is to always have equipment we use always capable of reproducing what the instruments are capable of. Think instead of always preserving, rather than removing,  because if we had attitude of removing we are then denying what is possible, rather than celebrating what is possible.

 

A good example is the recordings done by reputable studios, which have been preserving sound well beyond the specifications of the equipment we use for replay today.  The outlook is when audio equipment ability improves, the recordings will similarly match. Rather than being fixated on outright technical ability of recording, labels like ECM  have preserved their piece of musical history to the best of their ability since 1969, which has encouraged them to use the best equipment possible.  

 

But it goes further than that, if we look at famous recordings like Kind of Blue ,Miles Davis there was real effort at providing the best possible sounding room.  https://en.wikipedia.org/wiki/CBS_30th_Street_Studio  Sadly now demolished the sound of the acoustic and of course the wonderful playing will be enjoyed possibly in a thousand years from now, given Kind of Blue remains the best selling jazz album of all time.  

 

 

[sir sanders zingmore]

A good analogy would be to always ensure we design cameras that can capture the microwave radiation from the sun. That way we can ensure no part of the spectrum is missed on the telly

Edited July 20, 2020 by sir sanders zingmore

[davewantsmoore]

On 20/07/2020 at 8:28 PM, stereo coffee said:

There is musical frequency content out to 102.4 khz

You can't reproduce (or hear) everything you can measure.

[davewantsmoore]

23 hours ago, Ittaku said:

That's correct. There are some scans of the brain done suggesting we respond to ultrasonic frequencies even if we can't tell whether they're there or not in blind testing, suggesting they have a "feel good" phenomenon associated with longer term listening that wouldn't be there without them, but that science has not been validated.

Indeed... but no practical speaker reproduces these types of frequencies.... or, if they do, with any level of accuracy so that people can expect the same evergy at those frequencies on different system.... or even different sides of the same couch cusion.

[stereo coffee]

4 hours ago, davewantsmoore said:

Indeed... but no practical speaker reproduces these types of frequencies.... or, if they do, with any level of accuracy so that people can expect the same evergy at those frequencies on different system.... or even different sides of the same couch cusion.

Indeed there will be natural roll off of upper frequencies in high frequency loudspeakers. However underlining natural roll off, rather than forced imposed roll off.  The very popular and famous Kef T27 tweeter, has frequency response to 40khz.

 

Where a amplifier  is deliberately designed with wide bandwidth, we see subjective reviews using words like this: 

" Stu Hegeman’s circuits produced a sound that had a life and a breadth and image depth that were stunning. They were the ultimate in soundstaging and sense of immersion."   http://www.theabsolutesound.com/articles/harman-kardon-citation-ii-power-amplifier/

 

" The Citation II’s circuit was most elaborate, the thinking behind it exceptionally advanced, the sound spectacular! It consisted of a pentode input stage, followed by a pair of 12BY7 video pentodes as a differential phase splitter (the video pentode supplied a bandwidth of well over a megahertz in the input stage). The video pentodes drove the grids of the output tubes to full power. This had never been done before, and it resulted in a wide power response that was second to none."

 

 

 

[stereo coffee]

13 hours ago, davewantsmoore said:

You can't reproduce (or hear) everything you can measure.

And you can't measure everything, you can hear. 

[davewantsmoore]

16 hours ago, stereo coffee said:

The very popular and famous Kef T27 tweeter, has frequency response to 40khz.

Sure.... but with significant error, and gross error off axis.

... and then there another octave and a half to get to 100khz.

Quote

Indeed there will be natural roll off of upper frequencies in high frequency loudspeakers. However underlining natural roll off, rather than forced imposed roll off. 

LOL.   The "natural" rolloff of almost all speakers don't them make signiciant sound at 40khz..... let alone without significant error.

 

I spent quite a few years doing quite a few experiments on this with ribbons and piezo devices (as well as domes) .... the initial aim was to find out what makes hi res tick... but that quickly reached the conclusion that it was nothing to do with response > 20khz..... and so from there it was just focussed on audibility of > 20khz.     Very difficult to sort wheat from chaff (ie. the old saying "when all else is equal") .... very interesting results. 

Edited July 22, 2020 by davewantsmoore

[sir sanders zingmore]

22 hours ago, stereo coffee said:

And you can't measure everything, you can hear. 

But the articles you cite (time and again) seem to have measurements. Should we ignore them?

Edited July 22, 2020 by sir sanders zingmore