[nick n]

Added another 4 more below the Philips.
 
^ that Sennheiser driver is making me want fruit salad now.
 
Philips 6326 ( no not 6325 single entry ) dual entry Electret - TRS jacked -  hence the crappy transformers in the cups.
Ready for a project transplant.
80 mm drivers!
the backplate  serves as the contact and retaining mechanism for the driver layers
should be the same as the 6325 which is
[size=small]Electret condenser type [/size]
■ Impedance 1000Ω
■ 20-22,000 Hz frequency band playing
■ 4V permissible input
■ 104dB/mW sensitivity


 
KOSS TD/80
 
55mm driver !
■ Dynamic Model
■ Impedance 60Ω
■ 20-17,000 Hz
■ 98dB SPL/1mW sensitivity
 

 

 
Sony MDR-XD200
 
Hugely angled 40mm drivers.
See the thin foam backed fabric that sits over the baffle driver opening resting on the cup bottom.

 

 
Interesting variable baffle vent flap can be shut or gradually opened up. Here it is taped open.

 
Side profile. Check out that angle!
 

 
Sony DR-5A
■ Dynamic Model
■ Impedance 8Ω
■ 50-17,000 Hz frequency band playing
■ 300mW permissible input
Massive fibre cone thing. Riveted to baffle which is riveted to cups.
 

 

 
Elega DR232-CH OEM'd ( Audiophile brand name obviously, also goes under the Mellow, Marantz,  name and a few others I forget at the moment
■ a dynamic two-way diaphragm type
■ Impedance unknown
■ 20-20,000 Hz
■ 100mW permissible input
■ 105dB/600Hz 1mW sensitivity
 

 
The awesome rockwool/fibreglass stuff again seen in Stax and many other older cans WHERE DO THEY SELL THIS STUFF???
 I wonder if this is the stuff that people have been removing from their ESW-9 Audio Technicas calling it "failed decayed cotton"

 

 

[vid]

Vintage (1980s) Beyerdynamic DT 990.


 
Not sure what material the membrane is, but it's sticky. There was a whole bunch of thin black fibres stuck to it from the black disc that covers the baffle; they were literally glued onto the diaphragm. (Hence my opening the drivers up - there was some hair-like distortion in the bass, which was fixed now.)

 

[GREQ]

Quote:

Vintage (1980s) Beyerdynamic DT 990.
 
Not sure what material the membrane is, but it's sticky. 

The stickiness is probably because it's slowly decomposing/rotting - the diaphragm might be some sort of rubber composite.
It would be curious if that wasn't the reason.

 

[Ishcabible]

Quote:

The stickiness is probably because it's slowly decomposing/rotting - the diaphragm might be some sort of rubber composite.
It would be curious if that wasn't the reason.

 
Don't the modern ones have sticky drivers too?

 

[MDR30]

Quote:

 
Don't the modern ones have sticky drivers too?

 
I have an old DT880 with sticky surface, probably from the 1990s, and a DT250 a couple of years old - also with sticky surface. Would be interesting to know if the contemporary drivers are the same.

 

[GREQ]

Quote:

 
I have an old DT880 with sticky surface, probably from the 1990s, and a DT250 a couple of years old - also with sticky surface. Would be interesting to know if the contemporary drivers are the same.

Sounds interesting. I wonder if it's part of the manufacture process, or a bi-product.

 

[jerg]

Hifiman HE400
 
 

 

[vid]

I think the Beyer driver stickiness is purely a result of the gravity of awesomeness in those drivers that's making things stick to them.

 

[dBel84]

Stumbled on your cool thread, I didn't see this one posted 
 
Denon AH-D6
 

 
Driver is a planar type , not orthodynamic but a flat compressed foam 
 

 

 
..dB

 

[MDR30]

Quote:

Stumbled on your cool thread, I didn't see this one posted 
 
Denon AH-D6
 

 
Driver is a planar type , not orthodynamic but a flat compressed foam 
 

 

 
..dB

 
What a find! Probably inspired by the contemporary flat loudspeakers (Sony, Technics, if my memory serves me right). But foam membrane?! Any chance of a better close-up?

 

[GREQ]

Vivanco SR76 driver - shiny! (probably just a generic cheap driver)
 

 

 

[GREQ]

Left: AKG K140 W
Right: AKG K241 

 

[vid]

Quote:

Left: AKG K140 W
Right: AKG K241 

 
Note the five dots in the middle of the K 241 driver, missing from the K 140. Fitz posted pics of Sextett drivers here: http://www.head-fi.org/t/202122/the-headphone-driver-pics-thread/60#post_3883163. Try to look for the five dots on those.

 

[GREQ]

Quote:

 
Note the five dots in the middle of the K 241 driver, missing from the K 140. Fitz posted pics of Sextett drivers here: http://www.head-fi.org/t/202122/the-headphone-driver-pics-thread/60#post_3883163. Try to look for the five dots on those.

You can't see them but the K140W has 3 dots: I took quite a few photos, but they just wouldn't show up.  
Also on the backs the K140W has the #2 imprinted, and the K241 #3.
 
Also it's worth mentioning that the K140 W's voice coil is an orange copper. My K241 and K141 both have red copper.
 
Incidentally the reason I could take these photos is that I replaced the K241 drivers with K140 drivers as I couldn't find a replacement for the faulty one. (kind of an experiment)
The sound is surprisingly similar. The main difference is the K140W is about 5dB less sensitive, the bass rolls off a little earlier with a little less slam and the treble isn't as piercing as the K241 can be.
Altogether when amped properly it actually sounds excellent (almost the same) , but through my PA2V2, there is a bigger noticeable degradation in quality and extension especially in the bass.
But for a home-only headphone it's really quite good. 

 

[vid]

I'm sure someone will have pictures of the Sextett drivers that show the dots better. On the K 241, you can't miss em.