[soundyseb]

ESS mark 1 AMT driver with busted ribbon :sadge:

 

[soundyseb]

ESS 422h DD & AMT tweeter

 

[AsciiJC]

The holy speaker

Looks pretty gorgeous if I says so myself!

 

[Muinarc]

Yamaha YH-5000SE driver. The ring magnets go into the "white" parts of the above photo.

 

[AsciiJC]

Yamaha YH-5000SE driver. The ring magnets go into the "white" parts of the above photo.

That driver has more networth than me.

 

[GREQ]

Sony MDR-V7 - 1987
Titanium Vapour Deposition

 

[Bingturong]

The absolutely beautiful Sony DR-M7 from 1979

 

[GREQ]

JVC HP-1000
35mm (diaphragm area)
38mm (silver ring)
52mm (plastic housing)

Also added a few pics of the cup interior because there are no pics on the internet.
The foam in the rear of the cup is in amazingly good condition.

 

[Bingturong]

Quite an interesting build, and quite a tall magnet too, I thought the shape of the earcups was just aesthetics but it really seems more functional

 

[Hoppy]

Pioneer SE-700 high polymer stereo headphones
Piezoelectric drivers from mid 1974 as date stamped on yoke

No twin holes in these like earlier post version has?
Foil is concave in picture, so convex/domed on side towards ear.
Wrinkles only there as foam was just pealed off after being on for an unknown number of years (49?). It disappears once foam is put back and removed again.
The foam is part of the driver and hold it taught so it doesn’t flap, almost like the speaker spider and rubber surround.
edit: the foam is actually 2 type, the outer small section with the 3 holes is like latex mattress foam, the inner is softer and larger bubble structure.

Drivers are only connected via contact with the small L shaped pieces of metal with a screw through them. They are not soldered directly.
Guessing one to top and one to bottom of the foil that coats the polymer, that would from a capacitor which is what these measure as.

Strain relief is a 1mm steel wire pinched tight. Seems very hand made and has plier jaw marks. Not even round like a split ring, it just bend wire U shaped and pinched shut.

Seems drivers and yoke are made and screwed together. Later the headband and wire is fed through the hole and out the slot in the outside plate above the mesh. It is then soldered, heatshrunk and then tucked down into the slot.

As it turns out, it's quite difficult to capture wafer thin aluminium coated polymer foil.
SE-700

 

[Bingturong]

Always makes me wonder why no one is manufacturing this type now. Construction wise it looks less complicated than an electrostatic but I can see it being more expensive than a dynamic or planar driver

 

[Max Choiral]

but I can see it being more expensive than a dynamic or planar driver

And the reason for that is?

Also, according to service manual it's not a good idea to open up 700's until absolutely necessary:

"More than 30 minutes's exposure of a high polymer diaphragm used in the SE-700 will affect its property, resulting in impairing the tone quality. Also never touch the diaphragm directly with the fingers, it will go ineffective. With these things in mind, be careful when disassembling the SE-700 for replacement of the cord, for example."

 

[Cifems]

I always found that instruction strange (but it still terrified me when I opened mine up)
The diaphragm isn't exactly sitting in a sealed housing, the back grill and foam are porous (so it's not a humidity issue?) and the diaphragm is even exposed through the holes on the earcup-side.

And perhaps the reason no one is trying a full range piezo driver is because... it just doesn't sound very good? lol
It's a unique sound for sure but tough as hell to drive adequately and not a great all rounder

 

[Bingturong]

I always found that instruction strange (but it still terrified me when I opened mine up)
The diaphragm isn't exactly sitting in a sealed housing, the back grill and foam are porous (so it's not a humidity issue?) and the diaphragm is even exposed through the holes on the earcup-side.

And perhaps the reason no one is trying a full range piezo driver is because... it just doesn't sound very good? lol
It's a unique sound for sure but tough as hell to drive adequately and not a great all rounder

Huh, I heard a lot of people say they're actually quite good and I'm still looking to get a SE700 myself.

But that high drive is an issue

 

[Cifems]

After relistening, I may have unfairly maligned the SE-700 by lumping it with the SE-300/500 in my memory. The bass for all three is extremely light, but the 700 is at least 'adequate', and has also a nice clear midrange and treble.

But to get back to driver pics, here's the Sony MDR-80T: