How to open DT770 pro?
Feb 2, 2009 at 9:29 PM Thread Starter Post #1 of 18

oluv

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the left driver of my DT770 pro 80 Ohm started buzzing around. i assume some hair got inside between the foam-cover and the driver because the buzz changes with different pressure. i also had the same effect with my old koss porta pro. first i also thought the driver was broken, but then i found some hair inside, removed it and it sounded fine again. i think it will be the same with my DT770 now. i removed the cushion already, but i have no idea how to remove the foam-cover. it seems to be fixed by the chassis somehow and i don't want to tear it apart. any ideas how i can open the enclosure without actually destruct it?

dt770fm9.jpg


thanks a lot for any hint!

o.
 
Feb 2, 2009 at 9:53 PM Post #2 of 18

cizx

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I opened my pair last year with a butter knife. Just use the knife to wedge the inner plastic ring up from the enclosure. It should pop right out.

You could always send it back to Beyer for service, too.
 
Feb 2, 2009 at 10:06 PM Post #3 of 18

apatN

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Feb 3, 2009 at 4:44 PM Post #4 of 18

oluv

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thanks all,
i opened them yesterday. took every hair out what i could find. but it seems the problem remained.
could it be that the wires of the driver start to vibrate with stronger bass and touch the inside of the enclosure? to me this sounds like a typical resonance sound, because when i took the driver out yesterday, i saw all the wires tangling around without any foam or whatever around them that could hold them in place.

i am still not convinced that the driver is really defective.

how secure is it stuffing some additional foam around the wires, so that they cannot touch neither themself nor the enclosure. or will this change acoustics?
 
Feb 3, 2009 at 9:19 PM Post #5 of 18

oluv

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i finally found it!
beyersmile.png
i was already desperate because i tried everything, stuffed some additional foam inside, but it was indeed a hair. it was already inside the driver, went through the paper-membrane but first i couldn't see it. then when i looked closer i discovered a little bit still sticking out, so i could pull it and an entire several cm long hair appeared. now everything sounds as it should. thank godness.
 
Jul 6, 2009 at 12:52 PM Post #9 of 18

selkin

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thx. there was a part where the screw driver could go in deeper. that's the spot.

the buzzing is still there, although I removed one small hair which was already halfway through the membrane..

should I open it remove the drivers as well or just send it back (if I can)
 
Jul 6, 2009 at 2:37 PM Post #10 of 18

Zombie_X

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There's probably a hair under the paper dome then. see if blowing into the dome helps.
 
Jul 6, 2009 at 2:47 PM Post #11 of 18

selkin

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as it turns out the warranty expired 2 weeks ago...

how do you mean blow through the paper dome ?

by the way, I can't really see how should I get the drivers out from the casing.. the sealing is perfect along the circumfarence, and also, what is the "protective mesh"? is that the paper dome we talking about?
 
Jul 6, 2009 at 7:31 PM Post #13 of 18

selkin

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edited. thanks for the helpful answer. (...)

I got it opened now. just had to force it a little.

it's not a hair under the paper dome. it's the dome itself touches driver's parts.
sad...
 

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