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DIY Hearing Test

ToTo Man

ToTo Man

the band not the dog
What's the recommended procedure for a DIY hearing test? In particularly interested in the SPLs the tests are run at.

I remember having a hearing test as a child when I started primary school and I don't recall the volume of the test being very loud. So, when doing my own hearing tests I have until now simply set the output level where easily audible frequencies, e.g. 300Hz to 8kHz are at a comfortably low volume through my headphones, and then I simply increase the frequency of sine wave in the REW signal generator until I no longer hear it, testing each ear separately.

Doing it this way, the fall-off as I reach the upper limit is very rapid. e.g. I can hear 13.7kHz but I can't hear 13.8kHz. However, if I raise the output level by a few dBs then I can hear 13.8kHz and a bit beyond. So I don't really know what volume to be running the tests at.

I recently got myself a miniDSP EARS for measuring headphone frequency response so I'm now able to calibrate a particular headphone to an exact output level, e.g. 75dB with pink noise or a 300Hz tone, but I'm concerned that playing sine wave tones at this level would damage my hearing. According to the EARS mic, I've been running my hearing tests at around 55dB.

PS - I do of course understand that headphones do not have a flat frequency response and that my choice of headphone will affect the result of my test. However, I'm not seeking to measure the flatness of my hearing but rather keep track of how it changes through time and spot potential problems.
 
I had a hearing test a few years ago.
There was a significant difference in high frequency reception between fight and left ears.
This flagged up a possible problem, acoustic neuroma being one, so I was sent for an MRI scan.
Happily it was all clear, but my ears respond differently to high frequencies.
 
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I used to get a hearing test every few years part of the medical for work. Ok part of a medical I get that. But I see no point on me knowing I have lost a bit of hearing which I have. Unless it's a drastic loss of hearing which you will know without a test. I enjoy listening to my music so dont want something in my head telling me I am not hearing the music right. Just a personal opinion we are all different.
 
My reason for wanting to test my hearing is a noticeable loss of HF over the course of the last fortnight, not just from my speakers but also my headphones. My hearing does tend to fluctuate so I'm not panicking yet but I am keeping an eye on it.

After reading interesting info here and here, I think I understand things better now, but the lowest threshold curve on this graph puzzles me. How is it possible to hear a sound below 0dB SPL, which presumably is absolute silence?!

EDIT - An anechoic chamber apparently has an SPL of between -10dB and -20dB, so it seems 0dB isn't absolutely silence but instead represents the quietest sound level an average human can hear.
 
Be aware of your sound exposure every day; you can get a short term frequency loss.

I got that from driving all day until i found noise cancelling phones; badly designed rag tops can be bad too.

I think high blood pressure can have the same effect.
 
There are on line tests you can self administer... that's how I know about the clever calibration by sound of rubbing hands together.... Sounds daft but works well.
 
ToTo Man said:
I do of course understand that headphones do not have a flat frequency response and that my choice of headphone will affect the result of my test.
Click to expand...
IME, headphones have a flatter frequency response than most ears. I attempted an online test with three different headphones. They all told me the same thing. My ears are anything but flat.
 
I'm still voluntarily shielding from C19 so shan't be frequenting any public places unless I absolutely have to!

I had my ears syringed about 10yrs ago due to muffled hearing and the difference was truly night and day. It was however a very hairy experience, I honestly thought the water jet was going to puncture through my ear drum! Keen to avoid another syringing I have used Almond Oil periodically to prevent another build up and inspect and clean my ears weekly to keep wax build-up to a minimum so I'd be very surprised if I currently have a wax buildup.

I suffered from ETD for many years but now suffer from PET and a mild and intermittent pulsatile tinnitus. It comes and goes. My ears have felt great the past couple of weeks which is what makes the lack of HF sensitivity somewhat puzzling.
 
If you note anything different in your hearing , go and see the man asap. If you´re lucky it will be a clogging up caused by wax but as in my case, I lost all hearing in my right lug in the space of a couple of weeks. A scan reveals I have a Schwannoma (v. rare benign tumour) so it won´t be coming back. Hearing aids are of no use at all. Back to Mono, although that does have its benefits : You stop worrying about your hifi and through cans and a mono extension lead you listen out for tonal differences and tonal separation of instruments which previously passed you by and the spatial bit is zilch.
No sir, my age has nothing to do with it - this usually affects people between 30 and 60 which includes me out, strangely enough.
 
ToTo Man said:
My reason for wanting to test my hearing is a noticeable loss of HF over the course of the last fortnight, not just from my speakers but also my headphones. My hearing does tend to fluctuate so I'm not panicking yet but I am keeping an eye on it.

After reading interesting info here and here, I think I understand things better now, but the lowest threshold curve on this graph puzzles me. How is it possible to hear a sound below 0dB SPL, which presumably is absolute silence?!

EDIT - An anechoic chamber apparently has an SPL of between -10dB and -20dB, so it seems 0dB isn't absolutely silence but instead represents the quietest sound level an average human can hear.
Click to expand...

The threshold of hearing (0 dB) is measured at 1KHz and is defined as 10^-12W per sq meter. Thats acoustic watts and not from yer amplifier. The phon graphs show how the sensitivity of the ear varies with frequency compared to the 0dB baseline. You can see that at 20Hz you need 10,000,000 times more power ( 10^-5W per sq meter) than at 1KHz to just hear that note! Hence why we tend to feel the vibrations of deep notes because of the enormous amount of power needed. However over the frequency range of around 2KHz to 6KHz the ear is at its most sensitive so we hear tones with a lower pressure than 10^-12 W per sq meter hence the negative dB values. For example -10dB is 10^-13 W per sq meter.

Maybe peeps can now see why a powerful amp is required if a HiFi system is to achieve realistic audio. How much depends on the sensitivity of the speakers used. Typical small boxes need loads of power whilst efficient i.e. very large speakers can get away with a few Watts. You need to turn amp Watts into acoustic Watts. My speakers are 0.3% efficient so 99.7% of the amps power is wasted as heat!

Cheers,

DV
 
Chris said:
If you note anything different in your hearing , go and see the man asap. If you´re lucky it will be a clogging up caused by wax but as in my case, I lost all hearing in my right lug in the space of a couple of weeks. A scan reveals I have a Schwannoma (v. rare benign tumour) so it won´t be coming back. Hearing aids are of no use at all. Back to Mono, although that does have its benefits : You stop worrying about your hifi and through cans and a mono extension lead you listen out for tonal differences and tonal separation of instruments which previously passed you by and the spatial bit is zilch.
No sir, my age has nothing to do with it - this usually affects people between 30 and 60 which includes me out, strangely enough.
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Hi Chris. Interested to follow your journey with having a vestibular schwannoma.
Back in Feb I lost the hearing in my left ear in the space of about 30 seconds ... without any warning or having any previous problems. It's been diagnosed as "Sudden Sironeural Hearing Loss" .. guess what you've also been suffering with. I had an MRI a couple of weeks ago to also check for a schwannoma and should be getting results shortly, but is probably down to having a virus back in Jan (maybe Covid-19 who knows!).
I've had some low-end to mid frequency recovery to the point where I can make out some sounds coming from the left channel, but guess I also have to get used to living life in the mono world! To lose stereo hi-fidelity hearing is a complete pain in the ass. Guess I need to look after my right ear from now on!
Maybe send me a PM sometime? Cheers, Nick
 
Darth Vader said:
The threshold of hearing (0 dB) is measured at 1KHz and is defined as 10^-12W per sq meter.
Click to expand...
Nope, the threshold of hearing is normally defined as 0dB re 20uPa or 20 x 10^-6 pascals. (Your dB reference is for acoustic power). It's a nominal level, arrived at by lots of tests in the 50s on healthy young male Merkans.

It's possible to have less than 0dB if the level is less than 20uPa. All things are relative in the world of decibels.

Hearing is generally measured with some kind of audiometer, and normally tests for your threshold of hearing. The threshold is when you can perceive a (typically) pulsating sound at different frequencies, and the 'reference equivalent threshold level' varies with frequency in a way linked to the equal loudness contours linked above. Those references vary depending on the type of test headphone used (Telephonics TDH-39 or Sennheiser DT48 - not exactly hi-fi) and are specified in a nice fat library of British Standards.

Some diagnostic tests also use warble tones and word recognition at different levels.

Your hearing will get worse at HF with age (Presbyacusis), but our auditory system tries to compensate, which is often why some suffer from tinnitus in later life
 
Nero said:
Nope, the threshold of hearing is normally defined as 0dB re 20uPa or 20 x 10^-6 pascals. (Your dB reference is for acoustic power). It's a nominal level, arrived at by lots of tests in the 50s on healthy young male Merkans.
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Yes. I tried to give a simple explanation and worked in 'Intensity' as most people can relate to Watts rather than to 'Pressure' measured as Newtons per m^2. When Intensity is converted into sound Pressure that 10^-12W per m^2 becomes 2 * 10^-5 Newton per m^2 which can also be called 20 *10^-6 Pascals. Take yer pick,

In a way its very much like power and Voltage the dB value is either 10log x/y or 20log x/y and this is similar for Intensity and Pressure.

I think for HiFi enthusiasts intensity is the easier with which to relate. As an interesting aside using intensity the threshold of pain is 120dB and that comes out at 1W per m^2. Also you can directly relate power output to acoustic instruments. For example if you bash a piano really hard you can get a peak of 0.44W!

Cheers,

DV
 
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Not sure thinking in terms of sound intensity is sensible. Time averaged sound intensity is a vector quantity and tends to zero as the reverberation increases. In a reverberation chamber, for example, intensity is close to zero, whereas the pressure (what we hear) can be very high. A listening room is somewhere in the middle, so it’s best to use sound pressure level as a parameter. your equivalence of 10^-12 W/m^2 intensity and 20uPa pressure only applies in a free field anyway.
Anyway, as you were.
 
Bob McC said:
I had a hearing test a few years ago.
There was a significant difference in high frequency reception between fight and left ears.
This flagged up a possible problem, acoustic neuroma being one, so I was sent for an MRI scan.
Happily it was all clear, but my ears respond differently to high frequencies.
Click to expand...

I suspect that's fairly common - I generally hear much better through my left ear than my right. Consequently I have the balance control set to give a higher output on the right.
That does not cure the problem entirely, because my 'bad' ear is actually more sensitive to high frequencies and much less so to mid/speech frequencies.
That leads to some odd results, for example I might get a sudden high frequency on the right channel which then sounds much too loud.
I also find classical music needs more of a right channel boost to make the image properly central.

I have had a proper hearing test and been told there's nothing to be done, and despite all that I do still enjoy listening, so I guess the brain is compensating too.
 
zippy said:
I suspect that's fairly common - I generally hear much better through my left ear than my right. Consequently I have the balance control set to give a higher output on the right.
That does not cure the problem entirely, because my 'bad' ear is actually more sensitive to high frequencies and much less so to mid/speech frequencies.
That leads to some odd results, for example I might get a sudden high frequency on the right channel which then sounds much too loud.
I also find classical music needs more of a right channel boost to make the image properly central.

I have had a proper hearing test and been told there's nothing to be done, and despite all that I do still enjoy listening, so I guess the brain is compensating too.
Click to expand...
Yes, don't underestimate the brain. The psychoacoustic thing is fascinating
 
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