0 dB SL is the minimum level at which the test subject can hear a stimulus, usually a tone pip. The actual level will vary with frequency. If we refer to a level of, say, 40 dB SL, we mean a sound that is 40 decibels above a test subject's threshold of hearing.

The dB HL scale is the mean dB SL of a large population (theoretically the world-population) of normal hearing people. They measured frequency-specific thresholds for alot of people, and averaged them to give the dB HL scale.

Finally, dB nHL stands for "normalised hearing level". This is the same concept as dB HL, except the number of test subjects contributing to the average is smaller. It is standard practice for a Hearing Clinic to establish their own dB nHL scale based on all the normal-hearing test subjects they have had access to. This allows a clinic to ensure that the scale they use is correctly calibrated to their test equipment.

Just found the App on FDroid and did a test. It went smoothly and I got my results. But knowing nothing about audiometry I don't know how to interpret them? Some kind of guide or at least a link to some resources would be very helpful.

Ideally the app would provide some kind of scoring or a rough comparison to what's considered "normal" at different ages.

It would be great for the user to be able to easily swipe thru the frequencies with fingers. For example to have something like two bars and a toggle on/off button.

1. The bars are there to swipe between the frequencies from low to high. Each ear with its own bar.
2. The toggle button is there to be able to swipe thru the frequencies with both bars (ears) simultaneous or separately.
   That way someone would be able to easily find out 1) if frequencies sound different and if yes, 2) how much the hearing is displaced (like 100HZ in one are vs 125Hz in the other ear).

In practice someone would have to swipe both bars simultaneous until he realizes that the ears hear the one sound different. Than he can press the toggle button to move the bars separately until the sound color on both ears matches again. The difference between the bars is how much the hearing is displaced.

I hope I have explained me well. If not just tell me and I will give it another try.

Best wishes,
Alex.

I got the above results. Could you please clarify the following doubts:

1. Can the test be done upto 20kHz as normal hearing can be upto that frequency?
2. My mobile phone doesn't have a headphone jack, so I use USB-C to 3.5 mm Headphone Jack Adapter - Apple. Do you think that this can affect the test results?
3. Why results are in hegative dB? What does 0 dB signify?

would allow for people to test how pitch correct they are and will help then adjust, you should hear a pitch, input a hertz, and then see how far off you are. also .apk on github for obtainium thanks

For use with an Android flip phone without a touch screen, please have the app accept a keypress as well as a touch screen tap.

While I was able to finish one full calibration, the app got stuck twice during the attempt to add a second full calibration. As a full calibration is a lengthy process, I have not attempted a third re-try.

Hi there,

a lot of these apps on the Google App Store have the feature, to use the measurement to turn your earphones into hearing aids.

I use this feature for the self-build hearing aid i made for my father. But sadly these closed source apps have a lot of downsides and anti-features.

It would be awesome if this app could be extended to pickup the microphone sound and play it back via the earphones with the option, of course, to apply the measured EQ to the microphone sound.

That way, this app could be used to turn earphones into hearing aid too.

Can't finish the calibration (both simple and full).

Here is the ANSI S3.6-1996 standard to convert dB SPL to dB HL.

https://hearinglosshelp.com/blog/understanding-the-difference-between-sound-pressure-level-spl-and-hearing-level-hl-in-measuring-hearing-loss/