Miracles in Audio, by luck, by good choices,by design or by tweaking...


I owned a low cost headphone for many years, the Fostex TH7B, first version( a new one close version exist Fostex TH7BK), semi-open headphone...I was never completely satisfied by any headphones I ever owned: Hifiman 400, Stax basic lamda, Stax 5 gold,Akg 340,Akg 701, beyerdynamic 990, and T150... Because in each of them with all their qualities I never listen to at the same times, a confortable headphone with natural timbre and voicing, with a good imaging and a realistic soundstage(not too close to my ears)...


For the last days I tweaked this Fostex, to damp his internal resonance I used sorbothane, I put some shungite stones at the exterior part of the cups and I use some Herkimer diamond in the interior pads( 3 at 120 degree) … Now this low cost headphones crush all my others if I sum all his qualities... For example his mids and voicing cannot beat the AKG 340 but among all my other headphones it is the best that is near that mids and it is more confortable, and with longer cable than the 340...His imaging is better and more realistic than the 340 etc etc...It is the same if I compare with the others...


His most important qualities is natural timbre and clear imaging,very precise pinned point accuracy and natural, so clear it crush for that ALL the others to dust...In the French audio circle the reviews were more than very positive few years ago...Diapason d’or and choc Classica...I am not the only one impressed buy the ratio quality/price... But remember that thesae reviewers dont tweak their headphone...The difference between before and after the tweaks are staggering...


Yes Miracles happens in Audio: cost is under 100 American dollars... Few years ago they cost me 50 bucks new... I never dreamed that I will go back to headphones...


I will enjoy your miracles stories of any kind ….My best to all...
128x128mahgister
If I think about it you are perhaps right, the effect is subtle ,not like my big  stones, and I had the impression that the sound is at the sames times clearer but more natural more transparent in a way that my big stones never give to me...I am amazed by that simple addition of micro-crystals... Perhaps the effect is so evident to me  in my system tweaked already, before all that tweaking perhaps this would had been way less audible...I dont know...But now I am happy, and in the headphone it is more extraordinary because they never sound so natural... I pinch myself because the Fostex TH 7 B is supposed to be  a beginners headphone not a  TOTL one... I think that will take big money to crush them on all count now... 
What is really helpful is a test tone track on a test CD and SPL meter to locate all the sound pressure peaks in the 3D space of the room. You would be shocked how many there are. Those peaks are where crystal should go. I found all audio applications for crystals almost twenty years ago. I wrote a white paper. 😬
I must act with a files but this experiment with pressure peaks is interesting...There exist methods of calculation for this but no room present the same accidental distribution or is perfectly squere or rectangular then we must need a SPL meter...
The sound pressure peaks are room and system dependent (radiation pattern of speakers, distance from walls, etc.) and the amplitude of the peaks is dependent on the loudness of the system. but generally speaking the peaks can often exceed the average loudness by 6 tp 9 dB. Some examples of locations where very high sound pressures occur - room corners, between speakers and behind them, first reflection points/areas, room echoes (wall to wall). Also, standing waves that can occur anywhere in the 3D space of the room.