The quest for flat frequency responce may be futile if you have age related hearing loss. Use DSP to find YOUR "flat".

[John Dyson]

On 5/21/2021 at 5:28 PM, firedog said:

I've been doing that for a while and it works well. 

 

The better programmable hearing aids can also do quite a bit of the work for you. They are essentially doing the same thing within the hearing aid. The advantage is that they can have a response curve that's matched to make up for your specific personal hearing loss issues.

 

I'd hazard a guess that many audiophiles over 50 would find they have mild to moderate hearing loss if they were tested. 

Some of you know that I have embarassed myself more than once on my project (having to do lots of A/B comparisons to reverse engineer.)  Unfortunately, I'd have to go to the audiologist 3-4 times per day to get a set of curves (really.)   My hearing goes from a good, normal response out to beyond 12kHz-15kHz, then back to below 9kHz through the day. Bass acts similarly, but at different times.

Just imagine the confusion that it had caused -- and some loss of credibility.

Luckily a few people have finally figured out how to let me know that the hearing loss is very inconsistent.   Once I can figure out what is going on, and get the variability through the day fixed, then such a scheme might be helpful...

This hearing variation has been totally crazy-making.

 

The idea looks great, and I wish I could use it (but make my own parameteric EQ SW myself :-)).  I am good at super high accuracy software.

 

 

 

[John Dyson]

The variability of old-people hearing (at least mine) is so crazy as to inspire true insanity.   I have given up entire on any idea of 'perceived' flatness, only using 'listenable' flatness as a double check.  As some might already know, my project is NOT about pure flatness per se, but has an incredibly variable frequency response that can be as wide as +-20dB over the spectrum, but only mirror imaging other processing that people have become accustomed to.  Whether or not one might agree that there is ubiquitious processing since the 1980s, almost any audio processing nowadays is multband, so there is NO sense of 'flatness' anyway, except in boutique and artistically controlled recordings.

 

My guess is that the only reason why there might be some plausible perception of flatness is that the *average* energy as measured over very short term intervals is very similar to the originating material.

 

Anyway, about 'perceiving' flatness, it seems to me like the only reasonable goal on my project is to hunt for 'tells' where the energy might become inconsistent over narrow frequency ranges, thereby create a kind of 'distortion' in the sound.   Eventually, the goal, once starting with a prospective 'flat' response, look for minimizing the distortions (time, amplitude) based on the proposed flat signal.

 

Therefore, I have finally determined, after at leas >5yrs of intensive experimentation and >10yrs of less intensive observation that 'flatness' is in the 'ears of the beholder'.

There is too much time variability, both in the short term >5seconds and the longer terms that even make A/B comparisons of details a good challenge, but not likely to be totally successful.   Maybe those with younger, less damaged ears and less 'befuddled' processing in the brain might be able to attain reasonable accuracy.   Alas, I used to have truly very good pitch, being able to call out music notes very easily.   Now, as a 66yr old person, I have NO pitch, only hearing modulation effects, distortions, etc.   Tones, not so much.

 

Perhaps, best from my observations:   YMMV (your mileage may vary), that is -- maybe a few can truly perceive flatness, but even if so -- relative to what?

 

John