Hi, I’m Phil and I tinker compulsively. Shocker, I know. I don’t care for sibilance in my headphones. The MF-200B is a pretty thing with reasonable build quality. I happen to like the looks of the 200B. Last year I bought with a V90-BHA 2nd hand for cheap along for the ride was a pair of MF-200B headphones. I used them in my office to add a little bit of fun to the suck of staying way late far too often. The 200B’s have sibiliant tendencies as a major flaw.
The tinkering started with felt and cotton gauze over the drivers. I did a little tinkering with the drivers in the 200B and finally decided nothing I could do to them would tame the treble.
I started looking at replacement drivers. I was thinking, what if I can get some of the drivers Foster makes for the E-Mu purple hearts? 40mm, carbon paper. I was looking at replacements on parts express and eventually found some drivers on eBay being sold by a seller in China. The drivers were intended for a pair of Onkyo headphones co-branded by some guy named Zedd. I think all he actually did was list desires and approve of the driver tuning. Onkyo and maybe their mfg partner did the actual engineering. Anyways said drivers have carbon paper cones rather than mylar. Still 32 Ohm.
After swapping the drivers out things were better but not quite what I wanted. No. More tinkering was clearly needed. At this point I began tinkering with increasing internal volume but leaving the housings vented to the outside world through the outside facings. I also made a few changes to the drivers in an attempt to encourage a little bit more bass production. This is quite the opposite of the 00 headphones the drivers are from. The 00 vents the enclosures into the volume within the internal diameter of the ear pads.
IN current form the 200B enclosures are sealed with more internal volume and less in the way of internal chambers. I removed as much internal plastic as I though safe and given the driver as much internal volume as I can without adding any machined rings of aluminum which may come later.
Equalization is still needed but not to cure the treble. Mostly to bring the bass up (smallish sealed enclosure) and make a minor adjustment here and there. I only use the 200B on my PC with a Modi 3/ Vali 2 stack J/J E88CC tube. Sadly this doesn’t make use of the balanced wiring and requires a single ended adapter I made from mogami 2893 and Neutrik/Rean xlr connectors. In windows I use an EQ program named PEACE to reduce much the frequency range down by 3-5dB and bring up the bass at 50Hz by +7dB peaking at +10dB near 35Hz then flat to 20Hz or so.
I’ll continue to tinker with my 200B headphones. It is entertaining to tinker and fumble through what makes for a particular sound signature. Maybe some day I’ll get them right.
What are your Cobbled/Bodged/Hacked headphones? Did you ever get them right enough? How many iterations, hours, tinker sessions did it take to get them there?