Re: 11 Bark channels

> fact that they appear to dynamically anchor to a prominent frequency, a point of view that hasn’t made it mainstream yet, it seems), so it is reassuring to see confirmation in others’ work as it probably means that the chosen direction is correct.

I remember that sentiment on my part, very clearly. We are in unmapped territory - or more correctly, we are entering territory where what others have already mapped is very jealously guarded by an industrial cabal.

So we are really uncertain about our own findings. And so I did actual measurements on hundreds of individuals. From all walks of life, all ages, and hearing abilities. And I found direct confirmation. 

I even found that the Crescendo processing, in personalized degrees, is pleasurable to everyone, even a young man, Golden Ear, mixing engineer at a sound studio in San Francisco. I was blown away by this fact.

Some producers over the years have contacted me about using Crescendo as a sound enhancing plugin on their recordings.

The situation seems so crazy to me, that I wanted to launch an FMRI study to see what is going on in people’s brains when listening through Crescendo. Perhaps it stimulates endorphins?

So, I am not jealously guarding any of this information. Fifty years ago, when I was very young and in College - I went to a private Engineering College. The currency of the engineering realm is Patents.

But I was one of five outliers in the College, 5 of 1,000 students, who chose to study Physics. And of those 5, I was the only one to enter Grad School in Physics. 

In that era, among Physicists, the seeking of Patents was considered gauche, and boorish, behavior. But as time went on, and science become more privatized, we were pushed into becoming “Profit Centers” for businesses. Patents are the coin of the realm. And I am somewhat embarrassed to say that I now have 2 Patents to my name. (Not embarrassed by the low quantity…)



> On Nov 4, 2025, at 02:08, Yuri Davidovsky <[email protected]> wrote:
> 
> 
>> On 3 Nov 2025, at 23:40, David McClain <[email protected]> wrote:
>> 
>> For good musical listening, my current system in the lab here is using 11 bands, each 2-Bark wide. And it sounds amazingly good to me. The band centers are identical to the standard audiology testing frequencies.
> 
> I am not through the article yet, it will take me a few days to figure it out properly, but you also seem to mention there that 11 bands turned out to work quite well for the purpose, which is good news. I have been long brooding on a potential side project that does binaural processing (in short, it should take a multichannel record and upmix it into spacial audio for headphones (similar to what AirPods do when you are watching a movie with a DTS soundtrack)) and could not come up with a ballpark figure of the number of bands necessary without experiments, for which I simply do not have time at the moment looking into things that are supposed to make money.
> 
> I was planning to start as high as 96 Bark channels per ear and see how low it could go while still sounding convincing (96 was chosen as it is 4x of 24 bands number that I came up with for the optimal number of Bark channels, so 1/4 Bark channel resolution would be the result) but it appears according to your research that a relatively low number of bands can be usable. Now, binaural processing can be more finicky as your spatial resolution will worsen as the number of available bands decreases but it appears that even a relatively small number of channels might work, according to your findings.
> 
> A couple notes/questions in relation to the parts of the article I went through.
> 1. As I understand, essentially the algorithm is fairly straight forward: we have a sensitivity drop in each band below a certain dB threshold and so we attempt to make up for this drop by applying gain to the affected amplitude range?
> 
> 2. You call it [dynamic] compression in the text, however it also appears that it could also be called expansion, where instead of making loud parts quieter we make quiet parts louder (in other words, instead of applying gain adjustment to the signal above a threshold, we apply the adjustment below it)? One could be expressed in terms of the other, of course, but I think expansion is a little more descriptive since compression often assumes making things quieter by its very definition.
> 
> 3. I did not quite get the single knob correction philosophy (might be because I haven’t gotten deep enough into the article yet) as according to what has been said you need to apply the gain to each band individually. Does it mean there is a linear relationship among impairments across the bands? Meaning, say if in a band centered at 4kHz we detect some impairment, each subsequent band will have more and more of it with some simple scaling factor applied? (e.g. the threshold increases by 2dB in each subsequent band, or something similar).
> 
> There is a bit of maths to wade through too but for now I want to understand the core principle behind the correction, hence the questions. An interesting part is that it appears I came up with a lot of the same findings in relation to how Bark channels work as you show in your article (like the fact that they appear to dynamically anchor to a prominent frequency, a point of view that hasn’t made it mainstream yet, it seems), so it is reassuring to see confirmation in others’ work as it probably means that the chosen direction is correct.