[WallofHooligans]

Another mini update- I've pulled out all of the bits that I intend on replacing. Unfortunately, the capacitor didn't want to come quietly, so I had to cut it's leg off, on both sides. I got a chance to measure the capacitance, and without knowing so beforehand learned that the value of a bipolar cap is half that of what is stated. As far as I understand, a bipolar electrolytic cap is actually just two electrolytic caps sandwiched together- I just didn't expect the uf value to reflect that. ANYWHO, the UNICON caps that were in there measured 28.3ish and 29ish microfarad. Double that and we get a few uf less than 60. The original value is 47, so that's good to know. I plan on replacing these with Nichicon Muse caps from the ES series. I put them above the voltage rating of the base caps (16v) just to make sure that my futuristic stuff doesn't hurt these poor cans from a different era. I'm also planning on bypassing them with a film cap, though I don't fully understand what value I should have picked. Seems like everyone has a different idea. I picked up two different ones to try out- I'll report in on my findings.

Speaking more outside the point- Why don't they produce little sheets of cones, so you can use the technology for an anechoic chamber on the inside of your headphones? I bet that's worth cutting 100 triangles out of foam to try out for myself

 

[karlsonklam]

that "box" on the alnico cylinder is the magnet's return circuit https://www.premierguitar.com/articles/Magnetic_Circuits
- can't remember the cap's value - I used a cheap bipolar electrolytic and wish had paralleled it with a bypass cap - maybe a Dayton 0.47uF film and foil. Mine has sat for some years after the re-cap but seems to be coming back to life with a day's play and is surprisingly dynamic using a $25 TPA3116D2 amp (Amazon) on percussion - try these tracks assuming you have clean power. (my Vali clipped & died on drums w. Koss PRo4AATi)

 

[karlsonklam]

that "box" on the alnico cylinder is the magnet's return circuit https://www.premierguitar.com/articles/Magnetic_Circuits
- can't remember the cap's value - I used a cheap bipolar electrolytic and wish had paralleled it with a bypass cap - maybe a Dayton 0.47uF film and foil. Mine has sat for some years after the re-cap but seems to be coming back to life with a day's play and is surprisingly dynamic using a $25 TPA3116D2 amp (Amazon) on percussion - try these tracks assuming you have clean power. (my Vali clipped & died on drums w. Koss PRo4AATi)

I forgot to say what a greast clean up and restoration job on the Dynaphase 60 that was done by WallofHooligans - in contrast I was lucky with mine being in pretty decent cosmetic shape.

Another thing, regarding "coloration", there seems none appreciable on the binaural recording linked below. With a modest $25 (shipped) TPA3116D2 amp which has a front headphone jack (and unknown series resistor), that recording is stunningly natural sounding. The low impedance of this headphone and many vintage cans, demands an amplifier which isn't stressed with 8 ohm or lower load. I can't get over how the wimpy looking paper cone "woofer" and little alnico magnet in conjunction with the "tweeter" * does a taut bass. (I've not tried hiphop/rap bass drops which
are synthetic vs bass vilola and bass drum) (* what does the tweeter look like ?)

 

[Reputator]

I thought I'd necro this old topic to talk about my recent modding on this headphone.

I've had them for a few years now, and I've already replaced the caps back in 2020, along with the earpads with these huge floofy memory foam pads from Aliexpress:

https://www.aliexpress.us/item/2255800222418541.html (115mm)



Highly recommend these pads as they fit the look of the headphone and are extremely soft and comfortable. They also sound great!

And of course I did the popular blue tack mod over the rear vents which is a literal requirement for good tight bass control if you own these headphones.



For comfort I had also opened up the headband and added some foam, since the original foam from the 70s had long since dilapidated. I sealed it up with a zipper which I glued in place, in case I ever want to swap the foam out again in the future.

---

Anyway, fast-forward to 2022, and my two most recent mods have been to replace the single-sided coiled wire with two 3.5mm jacks.



These 3.5mm jacks are the kind with the little screw-on nuts, and I tried drilling holes just for that, but they interfered with the drivers on the inside. So I had to enlarge the holes so the jacks would stick out more, and added washers to space them out.



Looks pretty good IMO, and fits the clunky shiny metal look of the headphone.

I left the stock wire going between the cups through the headband in place as I just like how it looks aesthetically. Obviously it's not connected to anything.

The washers were superglued on the outside and then inside I used plumber's putty to hold the jacks in place.



I got a navy blue Periapt cable on the way to complete the look, but for now I tested it with my Arya SE's old stock cable, and the new jacks work great! I swear it's actually punchier now, but there's no way to A-B it.

The next mod I did just today was to focus on internal damping. Most people stop at the blue tack mod which is fine (though new pads are a must IMO), but they can still exhibit some midrange shoutiness, and the cups are very resonant.

I had some leftover strips of foam maybe 0.5cm thick, so I cut a couple circles just under 4cm wide (about 1.5in) and stuck them on the back with double-sided tape.



The thick metal "box" on the back of the drivers rest right up against these foam circles, and I really didn't notice much sonic difference. So I kept going.



I placed a couple thin strips maybe 2in long on either side of where the openings on the "box" are positioned. I'm not sure the placement mattered but it made some small amount of sense to my dumb logic, so that's what I did.

The result is exactly what I was hoping for. The midrange is a lot more "controlled", in the sense that you don't get those resonant frequencies particularly in the upper midrange. Less honk, less shout, a little more natural and life-like and a bit closer in line with my better-sounding headphones. They're nicely elevated with this damping mod I'd say, so I highly recommend it!

I'll update with pictures when the Periapt cable arrives.

EDIT:
Here it is with the Periapt cable. A VERY substantial cable!