[Moonwalker]

Hi!

Could you tell me if your cans have vented magnet systems? For example, my HD-600 and HD-650 have vented magnet (ring), and my MDR-F1 have it as well. I can literally see trought the driver magnet. I wanted to know if Beyerdynamic cans like open design DT-990 or semi-open DT-880 have this feature, or other hi-end cans like AKG K-601 or K-701. Have this feature some advantage / disadvantage over more common solid magnet disc?

Thanx
Moonwalker

 

[sgrossklass]

Very good question. From what I've gathered, there could be these reasons for this kind of setup:
1. Dipole-ish radiation pattern, more similar to 'stats and such (or related to the microphone roots perhaps?).
2. Adjustment during assembly. (hwc's theory)
3. Influencing the resonant frequency.
4. Combining 1 and 3: easier driveability (the driver has to work against a smaller resistance, which should help efficiency).
Going from point 4, perhaps the diaphragm/voice coil assembly is so light that comparatively little damping is required, and damping could not be reduced this far in a conventional vented driver with a closed magnet. It's all speculation on my part though.

 

[Moonwalker]

thanks sgrossklass, for your input about this unusual topic!

I just find it strange, that many good sounding phones have apparently solid disc-shaped magnet (Porta Pro, PX-100) while some earbuds (Sony MDR-A34, E931 and others) with some other good cans like Sennheiser HD-650 have this feature. I'd like to know if some other headphone manufacturers like eyerdynamic and AKG used this system in order to improve sound or discarded it for some reason - maybe it's difficult to say if the change would be solely positive, for example the solid magnet would have grater strenght to attain graeter sensitivity of the driver???

Just my thoughts

Moonwalker