[RUMAY408]

  try this:
http://wegavision.pytalhost.com/sennheiser.html
 
sometimes this has translation issues :
http://translate.googleusercontent.com/translate_c?anno=2&depth=1&hl=en&rurl=translate.google.com&sl=ja&tl=en&u=http://20cheaddatebase.web.fc2.com/sennheiser/sennheiserindex.html&usg=ALkJrhjxp2iBTuflMhgB2pDnupkTRZp19g
^here will have the dates and specifications even if the translator is goofy

Very cool 

 

[Mr enig]

   
And solutions

 

Spoiler: Warning: Spoiler!

Left: Audio-Technica ATH-AD9
Center: Audio-Technica ATH-A9X
Right: Zenith Unknown Model

Curiously I wasn't able to find any info on the Zeniths in English even though it's an American brand. Yes in Japanese though: http://organ1969.exblog.jp/21724989/.

The unknown Zenith seems to be Model 839-43
http://future-forms.com/portfolio-item/zenith-839-43-headphones/

 

[DisCHORDDubstep]

So I was telling my teacher about my vintage cans, and he says he has one even older than the stuff I have... He goes to his desk, and pulls out these.
http://m.imgur.com/t1Wn4CA,R5UZAia,HTwxGMX
Not too bad! Only slightly n-shaped response. Great soundstage, good positional cues (the angled drivers might be helping with this)
... And they actually have some bass!

 

[agonynine]

APPEASE THE GODS

 
Wow, that is beautiful...

 

[takato14]

Received the Hitachi HD-S9.

One word impression: LOL

Photos and details later. I work early tomorrow.

 

[nick n]

talk about ambiguous!

 

[GREQ]

Probably because it sounds like poop.
Transients = above average
FR = WAAAAY below average

 

[takato14]

  Probably because it sounds like poop.
Transients = above average
FR = WAAAAY below average

Yep. I literally burst into laughter when I heard these for the first time. But before I get into that, here's my work log: 
 

 
This is how the cable looked when it arrived. This is due to the aging of the copper inside the cable; it has thoroughly corroded and taken the sheathing with it in the process, causing it to literally slide right off of it. From there the super cheap litz wire wore out. Really don't get why manufacturers thought Litz wire was of dire importance back then; every mid-high end headphone from the 80s uses it. And they all wear out and break. But enough ranting. 
 

 
I split the plug housing with a razor without breaking it in half, so as to preserve the original look of the plugs. 
 

 
Actually pretty intriguing design for this, the cable snaps into place and the wires wrap around the sides. Unfortunately this leaves no reinforcement joint, and the rubber is not moulded onto the cable, so the strain is placed directly on the solder joints. Bad.
 

 
Resoldered and plugged in. It's not pretty (yet) but it works. Before even thinking about trying them, I tested both channels with a multimeter. Exactly 100.1 ohms DC on both channels. Again before listening to music, I plugged these up and did some quick sine sweeps. This is to test for other forms of driver damage (excessive distortion/buzzing, etc). This is standard procedure when I get something that's in poor shape. Don't want to listen to something that's only half working and end up loving it. It passed, so it's on to foobar we go.
 
Oh god.
 
It was 10 seconds before I had to pull up the EQ, and it took me a solid 10 minutes of playing around before finding something that was tolerable. 
 

 
This is what I settled on. Yeah. Absolutely massive even order distortion throughout the bass and midrange; super thick, dense, and syrupy sounding. Something can't be right in there. Investigating. 
 

 
It appears to be a different design than the HD-9 based on what you told me, GREQ. There's a switch on the bottom of the cup, which adjusts an axis on which the baffle plate rotates; this is to make the pads seal better since the cups are mounted on a diagonal axis. Quite a prime example of form before function; this would be completely unnecessary if the cups were on a standard axis. Immediately after putting these on, even with no music playing, you can hear the resonance caused by the lack of seal between the cups and baffle plate. Seriously stupid design, no wonder this thing is so rare. 
 
I was able to twist it off with relative ease, however. 
 

 
Ok, yeah. That'll do it. The driver is dampened WAY too loosely due to the way the foam in the cups has aged. Gotta love the 80s.
 

 
Yuck. That's actually supposed to be two layers of foam, but they've merged together. This is literal powder at this point.
 


As GREQ predicted, the driver is clipped into place. As he ALSO predicted, the plastic snapped immediately after being disturbed. This thing really ages like ****.
 

 
The driver is covered in little bits of foam from the pads. Nice.
 

 
Cleaned off and in better lighting. I sense some potential from these pretty little drivers so I'm going to try a few things with them. I've still got some dynamat left over from the HD700 and I'm likely going to have to 3D print a new baffle plate due to how incredibly poorly these have aged. 
 
---------------------------------------
 
***In case it wasn't clear, here's an FYI to any potential owners: This is a headphone that will require loads of T.L.C. before it becomes anything even close to usable. I already for sure need new pads, new damping foam, AND a new baffle plate. This is a project headphone and it should be priced as such. No matter what condition you find these in, don't pay a lot for them. They WILL require extensive work. I've seen pairs on the internet for $Hell.No prices and thought I should make that clear.

 

[nick n]

excellent post takato(14).
 
Before messing with Dynamat and spending large $ on some, unless you already have some, look over yonder in the high end section here for the Damping With Sorbothane thread.
You might be glad you did.
It does something Dynamat can't and a small sheet of say 30D 1/10 inch thick with the preapplied 3M adhesive is a lot cheaper than DMAT.
It might even help that ongoing secret 700 mod of yours.
 
http://www.head-fi.org/t/744839/damping-mechanical-resonance-distortion-of-stax-and-other-phones-with-sorbothane
 
 
These will live again, they must have some potential.
 
 
ouch on the EQ curve, just...ouch
 
speaking of ouch potential get yourself a thin blade exacto knife and ditch that steak knife!

 

[esko467]

Just got my Sennheiser HD 414 headphones! It has yellow foam ear pads from Custom Cans UK. It hadn't survived with original pads.
Perhaps that's good thing considering the age and dirtyness they could have had
 
I am currently listening these with laptop as source. I used 6.3mm to 3.5mm adapter.
At first only one channel was working and low voiced. After rotating the plug(s) they started to work.
 
Sounded muddy almost like behinds the planket. Trebles were bit too high, also. After I edited the equalizer a bit in foobar2000, it started to have more bass and nicer treble. The more I listen the more I like them. Later on, I need to plug it into Oppo HA-2 and listen the difference it might have.
 
They fit really nice over my head. They are light. As Open-Aire headphones they leak music so perhaps not for commuting but for home use they fit perfectly if you are into vintage headphones an Sennheiser.
 
Thanks for reading.

 

[takato14]

Just got my Sennheiser HD 414 headphones! It has yellow foam ear pads from Custom Cans UK. It hadn't survived with original pads.
Perhaps that's good thing considering the age and dirtyness they could have had

I am currently listening these with laptop as source. I used 6.3mm to 3.5mm adapter.
At first only one channel was working and low voiced. After rotating the plug(s) they started to work.

Sounded muddy almost like behinds the planket. Trebles were bit too high, also. After I edited the equalizer a bit in foobar2000, it started to have more bass and nicer treble. The more I listen the more I like them. Later on, I need to plug it into Oppo HA-2 and listen the difference it might have.

They fit really nice over my head. They are light. As Open-Aire headphones they leak music so perhaps not for commuting but for home use they fit perfectly if you are into vintage headphones an Sennheiser.

Thanks for reading.

The Oppo isn't going to be much better than your laptop most likely. You'd be better off with an OTL for those old senns; they are 2000 ohms and require a huge amount of power.

 

[esko467]

The Oppo isn't going to be much better than your laptop most likely. You'd be better off with an OTL for those old senns; they are 2000 ohms and require a huge amount of power.

 
takato14, you might be correct. I have to crank up all the volumes in my laptop to get sound. iPhone was bit quieter than laptop. Let's see what amp does or does not. I could try my Naim as well later.
 
Actually these were the HD 414 X versions, judging from the photos of User's Guides of HD 414 and HD 414 X. 
What actually impresses me is that how good they sound. I remember when I listened these in the 80s.

 

[ATau]

 

[takato14]

Some progress with the HD-S9:
 

 

 

 

 

 
Got the prototype print in the mail today. Turned out very nicely, the scale is perfect and it fits the cups exactly.
 
However, the driver cannot be mounted in with the mesh screen in place due to how the hinge works. Its a YH-1 type hinge and the arm sticks into the cups a considerable distance. Thus I adjusted the tolerances slightly to give myself ~4mm extra clearance in the cups. This should give me enough room for the damping too. 
 
I ordered two this time, in the black variety, and will provide more pictures when they arrive next week.

 

[nick n]

Nice work looking forward to some favourable results.
What an awesome part you got made.
Take long to draw it up?
And is the center design based on anything else like a sennslimer perhaps?
 
Do you figure the front mesh adds anything  to the tuning. I wonder if you could simply stretch some acoustically transparent sheer fabric over the front instead of bothering with the mesh, and maybe a further thin foam to tune and add additional protection.