The Headphone Driver Pics Thread - Page 18

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. 

Edited by GREQ - 10/2/12 at 7:56am

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.

Just a few cheap dynamic drivers on show here.

 

From left to right:

Sony DR-7 -- Universum 349540 5 -- Philips SBC 3150 -- AKG K241 (for size comparison)

 

Sony - surprisingly better than A LOT of modern cheap headphones - very warm sound.

Universum - these are hilariously thick and heavy. The diaphragm is quite thick. Sounds horrible.

Philips - needs very careful tuning, but nothing special. 

Something a lot more juicy than my previous post - Rank Arena SK-600 drivers.

I believe they are dynamic drivers with an aluminium membrane/diaphragm. (outer diameter 75mm, inner diameter 60mm)

 

 

 

Sennheiser Unipolar 2000. Entire diameter ~104 mm, driver surface diameter ~90 mm. The front looks the same but without the disc in the middle.

 

Closeup of ear gunk on the protective plastic wrapping.

*I've made a thread for my post: http://www.head-fi.org/t/636893/help-me-figure-out-the-hp-1000-driver-the-black-moving-piston-part-in-the-back

 

Thanks to those who took the time to read it anyway ;)

Edited by devouringone3 - 11/18/12 at 5:33pm

not often seen, if at all, P.W.B. Moving Coil M.C.3. ( Peter W. Belt )

 

 

Unknown specs, date possibly very late '70's

This is from the Grey model, I have seen, but do not own,  a P.W.B. Black Moving Coil model also. Unsure which one is the exact one listed in the catalog sheet dated 1978 ( scan for that PWB stuff seen in the Ortho Roundup thread )

 

Ring magnet. Surrounded by foam, also the center dark spot is foam

Mylar dynamic diaphragm .

 Black driver housing measures ~56mm outside edge to outside edge. Big driver cannot see the edges looking through holes in front.

very thick wiring in the cables.

OOOPS  I should have tested the driver impedance when i was resoldering them. Someday.

 

 

anyone seen a vintage driver of this design that might help narrow it down?

Edited by nick n - 12/4/12 at 6:33pm

 

Those look VERY similar, if not the same as the two big drivers in the middle of my photo below: (3rd from the right)

Printed on the back is : "Japan DR0070 400Ω"

wow reallly close.

 even the large solder tabs there with the orangey-brown below them.

You mention cheap, do you recall what they came from? Oh I see Universum. That German brand.

 Just wondering because this guy ( P.W.B.) usually dealt with stax/Audio technica stats drivers, and being very eccentric I don't think he did anything halfways or approaching cheapo, these might be the exception though.

 

These have a vintage slant to them but not entirely hideous sounding

 

Thanks for this, what are the odds they would be randomly posted a couple of posts earlier in here, if they are indeed exactly the same. I'll have to look at the front side

Edited by nick n - 12/5/12 at 5:17pm

AKG Q701

 

 

Pioneer SE-90D, '80s.

 

 

Pioneer SE-90D, continued.

 

 

The metal driver guard (left) cannot be removed without breaking the driver (yep). The four slots surrounding the center of the metal guard are covered by a small metal ring (top) that had been glued onto the driver guard seemingly as an afterthought. The measurements I did say that removing the metal ring decreases the treble around 10 kHz by several dB.

Edited by vid - 2/23/13 at 6:51am

Sennheiser Momentum. 
Sorry it's not photos of the bare driver. I would like to keep my warranty intact. 

 

 

 

Probably been posted, but here's a bunch of KOSS Pro/4AAA drivers. There are 3 different series of drivers, and are in EP, MP, and LP production models respectively.

 

Series 1:

 

 

 

 

 

Original KOSS Pro driver from the mid 70's. Very intriguing design with a large voice coil and a fairly thick diaphragm that isn't glued down, but instead held in place by a metal ring. The plastic housing follows the shape of the diaphragm, leaving a small gap of air between the two parts. Has a very large, heavy magnet. Great soundstage, incredible bass, lush mids. Somewhat recessed treble. Very detailed. A very powerful sound with no peaks or resonances. Original paper damping deteriorated and was replaced with fleece. 

 

Series 2:

 

 

 

Redesigned version of the series 1, in production somewhere between 1978 and 1979. Rarest of the three. Has three bass ports instead of four, and foam damping instead of paper. Diaphragm has the same shape but is very slightly thinner. Thinner plastic housing, but a larger magnet. Unsure of the sound; this driver was broken when I got it. I'd guess more detailed, maybe slightly less bassy.

 

Series 3:

 

 

 

Newer driver from the 80's, completely redesigned. Much plainer in appearance. Smaller voice coil and thinner diaphragm. Smaller, lighter magnet. Bigger soundstage but worse everything else. Peaks everywhere. Has the horrible tin can veiling so common in headphones from the 80's. No detail. This driver was used in all "Plus" models of KOSS headphones, and was in production until some time during the 90's. This is the driver that killed KOSS's reputation as a headphone manufacturer. Funny how they put it in the best headphone they ever made until the ESP-950.

Edited by takato14 - 3/10/13 at 12:08pm

Most interesting and enlightening. First version makes me think of the Pioneer Monitor 10 diaphragm which also wasn't glued/fixed but attached with some foam.

Development doesn't always proceed in a straight line...