AKG K241 - 'Sticky' driver only starts playing on high volume

[GREQ]

My vintage AKG K241 'last sextett hybrid' has a 'sticky' driver.
 
It seems that when it stops playing for a few minutes the driver gets 'stuck' and will only start playing music again if the song has considerable bass at moderate volume, or I turn the volume up quite high for a moment... then it becomes 'un-stuck' and it's business as usual.
 
Has anyone ever heard or this problem before or experienced it?
Is there a way to fix this problem without replacing the driver, which actually sounds perfect once it gets going.

 

[GREQ]

*le bump*
 
anyone?

 

[zazex]

I strongly recommend you phone or email AKG.
Phone is generally faster.
 
http://de.akg.com/homepage-akg-de.html

 

[GREQ]

Quote:

I strongly recommend you phone or email AKG.
Phone is generally faster.
 
http://de.akg.com/homepage-akg-de.html

It's a 32 year old headphone, so they won't have replacement drivers or much advice on such an old headphone.
This is more of a DIY repair question.
 
Plus I've dealt with AKG before and their service responses are usually unhelpful.

 

[vid]

I've no idea about the stickiness, but what do you mean by hybrid?

 

[GREQ]

Quote:

I've no idea about the stickiness, but what do you mean by hybrid?

The K241 isn't a true sextett, but looks almost identical. Instead of 6 diaphragms, there are 6 ports with some sort of soft membrane (like coffee filter paper) which supposedly act like 'bass traps' producing similar sound to the sextett but at a much cheaper manufacturing cost. They are also the first ever true 'diffused field' headphone, the original sextett was not.  
It was a very short lived design, so it sticks out as being kind of an experiment headphone, a 3 way cross between the sextett and standard K240's and K240 Diffused Field Monitor that came after.
 
More news on the stickiness - giving the headphone a little tap with my finger also releases it from it's 'stuck' position.

 

[vid]

I wonder if the driver cuts out when you pivot the cup?
 
The K 241, while maybe not long-lived, managed to also spawn the K 250, which uses a similar (possibly the same) driver but has a more neutral bass and a different soundstage; likely a studio version of the K 241. Somewhat like the K 240 Monitor/DF dichotomy that came a few years later.

 

[GREQ]

Quote:

I wonder if the driver cuts out when you pivot the cup?

Nah, it's nothing like that - when I bought these, they were in a 'faulty state', so I did a full disassembly and cleaning. At first I thought a resoldering/recabling of the right ear would solve it, until I did a big volume track and it dramatically popped into life.
 
 
So the past week I've been playing a lot of bass heavy music on these to get the driver moving - perhaps there's just a piece of dust inside the voice coil or something... but either way the driver still cuts out occasionally.
Actually compared to a week ago it's a massive improvement - It cuts out less frequently and the sound is more constant on lower volumes, but now the driver slowly decreases in volume and then cuts out... but I fear I will need to purchase a new driver either way.
 
Does anyone know where I can buy a RED K241 driver? If it helps, I can open it up and look for the code on the back of the driver. 
Until I can source one, I'll continue doing these bass-heavy, loud volume burning sessions.... it might get better yet... or even cured. (fingers crossed).

 

[vid]

I'd say a physical driver and wire check is something to consider anyway. The wires connecting to the driver were not very secure on my 241 - one of them broke off about by itself once the driver was out.
 
Send a polite PM to Fitz, maybe he still has some drivers, though it's doubtful. The drivers on my 241 are almost perfectly matched, same for the K 250, which means that AKG either had very accurate production or did some amount of careful driver matching for these models.

 

[GREQ]

Quote:

I'd say a physical driver and wire check is something to consider anyway. The wires connecting to the driver were not very secure on my 241 - one of them broke off about by itself once the driver was out.
 
Send a polite PM to Fitz, maybe he still has some drivers, though it's doubtful. The drivers on my 241 are almost perfectly matched, same for the K 250, which means that AKG either had very accurate production or did some amount of careful driver matching for these models.

The last time I sent polite PM to Fitz, it got politely ignored...not sure I'll go down that road agian.
I don't know if I can do much about a physical inspection - it's not even possible to open up the drivers is it? If I could I would probably give it a go but I havn't seen anything like that in the forums/pictures.