[edulov]

Sorry to hear, but listening not to loud is a kind of common sense as-is, not even talking about long sessions. Your sound level was not deadly, just quite dangerous. Hearing will be restored, but w/o having earlier checks it will be difficult to find to which extent. Since I stopped listening loud music many-many years ago, I discovered the same effect (even at moderate loudness level) after listening bass heavy headphones with really extended bass. About 20min and I feel myself deafened for several hours (more then 4hrs).
The only reason behind this is biological. Frequences between 14Hz and 32Hz are related with brain activity and 15Hz and lower affect functions of human cells (loud infrasound sound levels).
 
Just to compare with sad stories, what I was able to check with my headphones and gear. 45 years old.
Lows: 6Hz Treble: at least 21500Hz (need better amp to go higher)
Resolution: 1/2dB w/o effort, 1/4dB, sometimes less in special tests with some training (I am audio fan, not musician, but some of my directly blood related relatives are tough in pro music/sound engineering)
Dynamic resolution (difference of levels of different voices/instruments in live track at my comfortable loudness level). Never did such tests on purpose since they depend much from amp and hp. But I know that this number IS BIG and this stops me from commenting some reviews here, becouse reviewer states headphone resolution as good or very good, but for me it is regular or worse. Bad hearing? Bad gear? Bad cables? Inapropriate test tracks? It also corresponds to some "heavy weight" head'i-fi'ers also.
 
Make fuss? But too many people have "normal" hearing; corresponding to the age tendencies, so from this point of view such reviews are valid. But taking it seriously - their recommendations only fool "lucky people" like me. And improve sells of the quite regular headphones.
 
Sorry If I have hurt somebody.

 

[cjl]

I'm rather skeptical of both your high and low frequency response claims. It's very likely that your transducers or something in your playback chain is distorting when asked to produce significant levels of either 6Hz or 21.5kHz, and you're hearing the audible distortion products, not the tone itself.

 

[edulov]

20Hz and backwards - lower lower and lower, different amps & hp's. Some hp's was unable to go so deep but I was hearing the same. For treble - also, but here it was much difficult, so I stopped where I was not sure that I heard any difference. I reached 21700, but can’t say if it sounded differently from 21500. Do not over think it. For me it means that all range 20 - 20000 should be taken into account.
Is not so perfect as you think, since I deleted many songs from play lists. I loved them for years, but after listening lossless with good amp and speakers/headphones I found to many flaws in play and mastering. Hopefully most others still shine.

 
I am not an audiophile, I want to enjoy music first of all. But it has two sides - bad equipment and LQ tracks. So in reality yes, I could be proud of myself, but also I am most unhappy man here, measuring things not in grades of enjoyment but minimizing levels of annoyance when I do critical listening.
You won’t trade places with me.
 

 

[catspaw]

I am not an expert in this subject, so take my answer with a grain of salt:
 
-How did you measure the loudness of the speakers? I ask because when you listen to music, in most cases the sound is not a constant tone at a certain decibel range, much less at the same frequency.
What I mean is, if you listen to 6 hours, and the peak in those 6 hours is ... say 100 db, most of the time you will have lower dB (silence between notes, lower volume notes, etc), so dont assume that your peak is calculated over 6 hours.
 
-What is the layout of your room? This matters as well due to the sound waves bouncing of the walls and coming back to you, increasing the total amount of dB or decreasing it depending on your location. This is a rather minor fact to take in consideration, but still.
 
The best thing is still to go to a specialist, no doubt. Forget internet tests, you have no way to validate their effectiveness, much less if your gear adds any coloration.