In my (from time to time) series with tech DIY guides (like the Pacemaker SSD upgrade) I will here post you a quick shorten/overview guide of my latest mini project. So here you go Sennheiser HD 25-1 (purchased some what 15 years ago) mini makeover.
I believe this post is for a smaller group of (nerdy) people, so I will write it in English. Enjoy!
Intro – why this restoration is needed:
- Glitching/loose headphone contacts.
- Very old and ragged/torn earpads/headpads
- Only 3,5 mm tele plug.
1. Glitching contacts
- Unplug the glitching contact (red or black) from the capsule (in my case, it were the red one).
- Careful put a thin needle down in the socket and push the small wire/spring a bit to the middle.
- Put the contact back in to the socket an test the headphones.
This video explains it very well: https://www.youtube.com/watch?v=EwKvHo2gCF0
2. Earpad restoration
2.1 Old look
This was old earpads. and yes not even usable at all in my (anyones) opinion.
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2.2 New ones
If you are struggling with the new earpads to fit your capsules. I unfortunately think you are do it in the correct way. I sat down for a few long minutes and even (carefully) used a fork before I got them in place. Maybe because I bought the non-original from Zomo, but then I got new headpads ”for free”.
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Finally I got them on the capsules and I am quite pleased with the result. Even if the headpads were a but cheaper looking then the originals. But as I mentioned, I think of them as free goods 😉 Hint: After a while the upper head bands lose the grip, so put some extra strong glue on ut right away.
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3. Tele plug upgrade
Tools I used: Solder iron, solder, solder stand, nipper, a knife (in shortage of a wire stripper), new phono (6,3) stereo plug …and thats it.
Tutorial (sorry for the image quality in this video):
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After good layer(s) of electrical tape I finally got it all in place.
Test sound:
No just kidding.
Use something like this instead to check if the soldering is correct: youtube.com: ”Left and Right Stereo Sound Test”
Final result
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Bonus: Sennheiser HD 25-1 history
(Update 2021-08 – To a new URL, from the old: youtube.com/watch?v=wB7Nhq5HQFA )