I doubt that's a cost cutting measure as adding that feature to the part increases the complexity of the plastic mold. Also the original Foster driver has those gaps aswell (you can see them for example on the Nighthawk). On fostex headphones you can't see them because the driver is embedded...

I was curious aswell, so I did some testing by myself. For this I used the working driver from an otherwise broken AKG K702 that I had in my closet: As mentioned previously all the AKG K500 derivatives have fully symmetrical venting. In the case of the K702 with the two slots for the surround...

Yeah, I think you misinterpreted my tone, lol. I didn't mean to be condescending whatsoever. I actually agree with you in that I love to see things like lead wires that are not glued to the diaphragm, symmetrical venting holes or no holes at all (like the Utopia), big center dome vents, vented...

Eh, I think you're overestimating the importance of radially symmetrical venting. You can mostly rectify rocking by simply increasing the permeability of the vent holes around the PCB as you can see in the picture you posted. Having symmetrical venting also does not account for non symmetrical...

Thiele-Small parameters (like xmax, qts, f0,...) of dynamic drivers for the lumped parameter model are usually measured using a Klippel rig that uses a laser vibrometer: Probably not intended for miniature transducers as the Sennheiser driver mounted on the helping hand is somewhat hacky. This...

You're right. They probably could have lowered the MSRP quite a bit by having it made in China. But instead they decided to have everything sourced from the EU, with critical parts being made right in the very expensive Vienna where they also assemble them. I appreciate this. I also appreciate...

MYSPHERE 3.1 Picture by Otwin: https://www.open-end-music.de/vb3/showthread.php?t=10791&page=27 wish I lived closer to Berlin...

That paper-domed Peerless driver looks super nice! I would stay away form metal coated mylar diaphragms, they are usually quite rough in the treble.

Nice! Did you rip the baffle's acoustic resistor off or did it come like that? Here are some pictures of the newer DT440s. They look alot like the DT250/DT150 drivers, however they are 32 Ohms and they kept the cotton dampener.

Hey Heinz! Could you also post the impulse response of some older headphones like the Sennheíser HD600 and the AKG K1000? I noticed the MySphere transducer sits very close to the ear, much more so than the K1000. I'd imagine that the decreased coupled mass ( in form of air) and the operation in...