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Beta Test: Earful -- a hearing test App

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pkane

pkane

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Thread Starter #101
So you didn't mean to use the RAW frequency responses of the database? Or yes and it, like you said, flatten the response?
Because if so it is kinda different than use a compensation curve based on the Harman target ones and indeed the results; from your flattening method to using a impulse filter (targeted to have a Harman curve), will be different for obvious reasons.

I was aware of that :) I just wanted to try the new function ;)
The raw measurement of the headphone frequency response (measured with no simulated ear, pinna, HRTF, and no Harman curves, etc.) will create a flat frequency response, compensating for any frequency errors of the headphones. That's what you would want to use when measuring threshold of hearing: flatten out the headphone frequency response.
 

zermak

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The raw measurement of the headphone frequency response (measured with no simulated ear, pinna, HRTF, and no Harman curves, etc.) will create a flat frequency response, compensating for any frequency errors of the headphones. That's what you would want to use when measuring threshold of hearing: flatten out the headphone frequency response.
I see but the RAW measurements available on the database are mostly (at least the ones from oratory1990 and the Reference Audio Analizer) with the dummy head which simulates ear/pinna also so they are not the ones you are looking for.
For example my hand/home made masurements on the KZ10 Pro I showed here in my old post (UMINK-1 straing on the memory foam tips) is the one you want I guess.
 
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pkane

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Thread Starter #103
I see but the RAW measurements available on the database are mostly (at least the ones from oratory1990 and the Reference Audio Analizer) with the dummy head which simulates ear/pinna also so they are not the ones you are looking for.
For example my hand/home made masurements on the KZ10 Pro I showed here in my old post (UMINK-1 straing on the memory foam tips) is the one you want I guess.
I could be wrong, but at least the InnerFidelity headphone measurements show the raw frequency response, uncorrected for HRTF or simulated pinna. Here's a description: https://www.innerfidelity.com/content/headphone-measurement-proceedures-frequency-response (the curve at the bottom of the chart is what we're interested in):

1596215518601.png


I was recently using Beats Solo 3 wireless headphones for testing. Here's the curve from AutoEQ website:
1596215653826.png
 
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pkane

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Thread Starter #105
Oratory's RAWs are different then:

You can see the gears he uses to get the RAW measurements.

Sorry, but where does he show how the raw measurements were acquired? They look similar to InnerFidelity, but I'm not really familiar with his process.
 

zermak

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It is written on the bottom of the image. That particular test was made on a GRAS 43AC/43AG coupler with KB5000/5001 anthropometric pinna. It meas the RAW data is with the simulated ear and so on (if you search for the parts numbers you will see what I am talking about).
 
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pkane

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Thread Starter #107
It is written on the bottom of the image. That particular test was made on a GRAS 43AC/43AG coupler with KB5000/5001 anthropometric pinna. It meas the RAW data is with the simulated ear and so on (if you search for the parts numbers you will see what I am talking about).
I see. So yes, a direct microphone to an acoustic coupler to headphones measurement of frequency response is what's needed for Earful.
 

zermak

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Ok, so what I thought since the begin :) and I suggest you to point it out then necasue many AutoEQ compensation curves are based on RAW measurements on simulated head/ears (even Inner Fidelity uses it indeed but maybe they share the RAW without the simulated head/ears; and well I have just seen the video in your link and indeed he said so but it's the program that compute the flat response curve from the RAW with the simulated head/ears).
 
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pkane

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Thread Starter #109
Ok, so what I thought since the begin :) and I suggest you to point it out then necasue many AutoEQ compensation curves are based on RAW measurements on simulated head/ears (even Inner Fidelity uses it indeed but maybe they share the RAW without the simulated head/ears; and well I have just seen the video in your link and indeed he said so but it's the program that compute the flat response curve from the RAW with the simulated head/ears).
By the way, here's a comparison I did a few years ago of HD650 headphones measured on my head with in-ear microphones, and with a simple acoustic coupler. Green is the coupler, red is my ear response to the same headphones:

1596218762252.png
 

zermak

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Nice and indeed it kinda reflects the measurements and what we know. The lower frequencies differences are probably due to the different sealing (headphones properly in your head vs coupler on some disc with hole I suppose) and the peaks at 2kHz it's becasue of the ear shape while the coupler and what you used misses that kind of shape.
 
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