A Real, Audiophile-Grade, Solution for Hearing Loss on All Devices

[middlemarch]

I have to modify my above comment a bit. While the installer told me the installation failed, in fact it did deposit the application into my Applications folder. Just now discovered it as I was looking for something else. So the app is there and it launches and appears to run. I can generate a test tone and hear it through my speakers.

Having said that, the user interface is a bit daunting. First, the window is a fixed size and can't be changed. Second, the app is about as removed from being "discoverable" as one can imagine. Nothing can be done without first reading the manual, probably several times. At first glance one has no clue what the app is actually for. So I will read the manual and see if I can figure anything out.

But, don't believe the installer if you get a failure. It's possible the app was installed anyway!

 

[Keith_W]

I forgive little niggles like that. It is beta software, and it's free. It would be different if it was paid.

OTOH, a virus warning ... that's something different. It may be a false alarm, but I am not going to take that risk.

 

[jjaskuna]

So lets say you connect a PC running your algorithm to a high-end headphone amp with its own volume control. How would you feedback information about the volume level back to your algorithm to do the correct corrections?

I would not feedback information in this example. I would need to know ahead of time the headphone amplifier and dac in use for the hearing test to calibrate the system under test. Then I would measure the system and include this data within the hearing test so it can adapt to the new calibration info. I would still include some qualifications for use, such as set volume output to XX% during testing. I should clarify that you do not need to use the DSP on the same device(s) used to test your hearing.

 

[jjaskuna]

Downloaded the app to my Macbook Pro. It failed during the install. Tried twice. Sent a message to the developers. Tried to send my system log file which details the install failure, but the message app on their website failed when an attachment was present. Sent the message without the log file. Have not had any response yet. Has anyone had success running the app, on any machine?

Thank you for letting me know. I will follow up directly with you.

 

[jjaskuna]

Just FYI.

View attachment 355279

Download blocked by Windows and automatically deleted. Please investigate and resolve this.

I also had a look at the user manual. I do not see how this is a "solution for hearing loss", it looks as if there are a number of presets (specifically, 12+1) that you choose subjectively to "match your hearing profile" according to the manual. I did not see any description of a method of measuring your hearing loss. I thought it may include a David Griesinger style DGSonicFocus which plays alternating tones which you adjust until the tones are subjectively equal in volume. This is why I wanted to download the software to have a look.

Will get this notice and delete resolved asap.

Regarding how it works, I provided more detail in response to @V17. Admittedly, the manual should include this info and more, which I will also address.

 

[Hayabusa]

I would not feedback information in this example. I would need to know ahead of time the headphone amplifier and dac in use for the hearing test to calibrate the system under test. Then I would measure the system and include this data within the hearing test so it can adapt to the new calibration info. I would still include some qualifications for use, such as set volume output to XX% during testing. I should clarify that you do not need to use the DSP on the same device(s) used to test your hearing.

Ok, but I assume your processing also needs to know the volume level while playing?

 

[V17]

Yes, absolutely. I was hoping someone would ask.

Here is the framework: Start with calibrated hearing threshold results spanning at least from 125Hz to 20kHz for a listener. Test more frequencies in the spectrum, not less. 4 frequencies does not provide enough information. Currently, the software uses template profiles and will move to user test results soon. Next, compare the test results against a reference, which is full spectrum from 0-20kHz (truly nyquist), to derive the users correction curves.

Here is a plot of my test results against the reference curve.
View attachment 355178

Currently, this is completed in a middle/sides optimization stage, not on the left and right channels. I've included two models of this optimization step, which apply different M/S models behind the "character" toggle. This will be fully tunable by the user and allow for additional modes, such as a decoupled stereo mode and a linked stereo mode. There are additional optimization steps governing the application of shared regions of hearing loss and those not shared. This is important for stereo or multichannel listening, as we are now listening in the environment and HRTFs become important considerations.

Next the filters are optimized or deisgned. Generally, we are tying to minimize the error between predicted and target response. Currently, there are both IIR and FIR embodiements with this one being an IIR topology. FIR is next and also presents optionality for things like phase specification. With IIR filters, operating rate can have dramatic effects on sound, so this is another tunable parameter based on what you feed in or if you use the "oversample" mode. This is a conveince feature. If you really want to experiment with different sample rates, turn it off and try different audio files or resample with something better--HQPlayer or Roon are options.

Apply the correction with the designed filters and then cascade (or remove) the dynamics and tuning sections. These aim to 1) control true peaks to prevent clipping in a musical way (user defines musical way, but we have some suggestions); 2) allow adjustment of the imaging post correction, as applying correction will modify the imaging perceived. These processing stages are optional, should one want to use just the filters. Within the dynamic section you can obviously control how the dynamics are applied, if at all, with the threshold, attack, release, ratio and knee parameters.

Re: Peace Equalizer
I'm not clear on what kind of filters they are using or how they handle freqs above 12.5kHz, as ELC is only defined to this point. It looks quite flexible, however, and seems to have some filter topology optionality, which I'm a fan of. I'm on mac most of the day, but I am going to give this a try. Here's my thought: audition using a common set of test results. If you want to try, let me know and I will share my tabulated results to compare in Peace and in my software--hearing profile #0.

One aim of mine is portability of test results and this is a strong use case.

Thank you! I may try it to see it in action, but as I afaik do not have hearing loss apart form what's expected in early 30s, I think it's likely not that useful for me.

I used Peace Equalizer because it allows me to theoretically flatten the frequency response of individual devices. When testing the audibility threshold of various frequencies, you are measuring the combination of the frequency response of the device and the frequency response of your hearing (loss), but since the latter is likely small in my case, I successfully used it to EQ headphones for which frequency response measurements were not available, and to check that my own edits to recommended headphone EQ based on measurements were sensible and making the headphones objectively flatter for my hearing.

As for how Peace handles frequencies above 12.5 kHz, it doesn't. I think it states that the method of finding hearing thresholds for each frequency does not work well in both the top octave and in the bass, and my own experience confirms this. But with headphones specifically I think that EQing both by ear is acceptable for a few reasons, though obviously not ideal.