[micon]

Strain reliefs are also different. Black strain reliefs were shortened when I recabled but you can still see the difference



The TDS-15 react very well to damping density changes. Their FR kind of reminds me of the Stax L500 (except for upper treble of course), here is the current lighter damping on the gray TDS-15 vs my L500. The Lambdas always have a bad seal on my rig, so the midbass bump and deep bass rolloff are exaggerated in the chart.

Spoiler: measurements vs L500

 

[micon]

I bought a lot of different models of headphones - ortho, izo, electrostats. of dynamic models, I was surprised only Sony R10. I noticed that many models had the same markings, but had differences because they were made in different factories. For example - English wharfedale ID2, Stax 007A>mk2, Japanese Yamaha HP-1 and YH-1. that's why I wrote that TДС- 7, 15, 16 were produced in different cities of the former USSR.
Аlas, I don’t do this now, you can only buy from good dealers who understand the difference between dynamic and ortho-iso

Caught another specimen, and it too has a difference.....
https://www.head-fi.org/classifieds/tds-15-isodinamics-rare.65771/

 

[Philimon]

Sansui SS-100

Seems to work fine and sound good. Fatter pads will add more v-shape response and increase comfort from deflated pancake pads... Ill probably use the same pads I used on T30 and RP18 which are the cheap but nice and pillowy hybrids pads. fwir they use twice as much wool damping as T50 or T30, Id rather not open these to confirm.

 

[Philimon]

SS-100 does not have any bass loss issues and channels match well. phew!

^ MiniDSP EARS, SS-100 (hybrid pads) vs HD650. The approximately 80mm diameter hybrid pads were just placed on top of stock pancake pads.

- Headband needs to be bent to make fit head well.
- Not enough cup rotation to make pads fit ears well without some headband manipulation which is common for the vintage.
- The cups / drivers look like they are floating in place.
- Headband says "omnidynamic".

I like less damping in general even though trade-offs for sure... I think Ill leave as-is considering Ive other headphones and because may harm future resale.

 

[Miiksu]

@Philimon That is impressive frequency response! Can u show waterfall? What pads? Cheapo chi-fi?

 

[Philimon]

That is impressive frequency response!

Indeed a good measure for my MiniDSP rig. Just the first pad I tried so Im sure frequency response measurements can be improved with other pads or mods. And Im sure subjective impressions too can be adjusted for as well.

Just like with other headphones, I feel less acoustic impedance damping is more preferable. I am tempted to open SS-100 and remove the wool but I hesitate because Im scared I might accidentally harm a rare beast in great operating condition. SS-100 dont come along at $240shipped very often.

Can u show waterfall?

Spoiler: Minidsp EARS, SS100 vs HE500

^ SS-100 cheap chi-fi hybrids VS HE-500 expensive chi-fi hybrids (Dekoni)

Spoiler: Minidsp EARS, SS100 CSD

^ SS-100 cheap pads

Spoiler: MiniDSP EARS, HE500 CSD

notes:
- HE500 seems to be particularly well behaved in treble for a Hifiman which might be why I liked more than HE6se (comparison)
- CSD decay could look very different with other pads and mods

What pads? Cheapo chi-fi?

Yes. Cheap and super comfy. A source. But beware, due to shape and depending on size they often fit supraaurally which is pro or con depending on your aims.

 

[Philimon]

^ Pilot pad installed and original pads removed and replaced. Comfort and fit are now good.

^ Definitely built to a premium compared to its cousins: T50 and T30.

^ That wide open grill and floating baffle is cool. The baffle seems to be held in place at 8 points that are tensioned just enough to hold the baffle in place but also allow some relief for head fitment.

First impression is that SS-100 is similarly competent as T50+T30. ime, the difference between T50 and T30 was former had harder hitting bass and the latter had smoother/clearer treble, I preferred T30 (until experienced some driver failure, good luck @Kabeer ). I am too lazy to search again, but I think @takato14 hypothesized that T30 had smoother treble due to the shape of its magnet structure with which SS-100 shares. Ill try comparing to T50 (RP18) and HE500 eventually. I still think SS-100 would benefit towards my preferences (increased bass) by removing stock damping material which I know is controversial move and accessing also increases chance for accidentally damaging so opting to refrain though then that might mean I have less interest in actually using SS-100 over other phones…

I would like to reterminate for balanced XLR so can utilize power of Jot2. I may ask for help on conferring correct wiring later…

A weak point for failure on these drivers is some foam gasket in the driver thats used for maintaining a seal. Its described somewhere earlier in thread with some description how to replace the expired foam. I know takato14 is well aware of the procedure and probably some others who may have also actually performed the repair too but I cant recall such as GREQ, Kabeer, khbaur, dBel84, etc. Anyways, the point is that if I open the cups to remove damping then that increases chances of disturbing the possibly delicate driver foam gasket and messing up bass and channel balance. i think, needs references

 

[Philimon]

I dont remember if this was mentioned here yet, but T50RPmk4 is soon to release with improved driver and other major quality of life upgrades. Biggest headphone news of the year imo, and maybe for some years to come with all the mods and limited releases. I was set to buy the new Stax SR-X1 but now that must wait for the imo likely superior and cheaper T50RP(mk4).

https://www.head-fi.org/threads/fostex-t50rpmk4-rp.972600/

 

[ludoo]

Also curious about the T50RPmk4, and given current preordes for the SR-X1 (which is for me *the* announcement of the year) will be shipped in July, I also plan on getting the Fostex as soon as it comes out.

 

[GREQ]

A weak point for failure on these drivers is some foam gasket in the driver thats used for maintaining a seal. Its described somewhere earlier in thread with some description how to replace the expired foam. I know takato14 is well aware of the procedure and probably some others who may have also actually performed the repair too but I cant recall such as GREQ, Kabeer, khbaur, dBel84, etc. Anyways, the point is that if I open the cups to remove damping then that increases chances of disturbing the possibly delicate driver foam gasket and messing up bass and channel balance. i think, needs references

In my RP18 I didn't replace the foam exactly, since it was only flat, but still a bit springy.
I precisely cut a very thin ring of fairly thin card (thicker than paper, but still quite thin), and added that underneath the foam.
Kinda surprised how well it worked TBH.

 

[Miiksu]

@Philimon Those earpads are good. I use it on modded Deva. Frequency response is flat like Sennheisers but slightly more subbass. But it still lack a bit of sub bass. Very good wireless headphone

 

[Philimon]

@takato14 or anybody,
Im not sure how to open SS-100 so as to access and remove wool damping behind the driver. I wonder if the outside grills can just be pryed off, but Id rather not try because am scared of permanently denting. And underneath the pads its not so clear how to open from that side unlike T30 and T50 where there were exposed screws and less tight fittings.

 

[Kabeer]

@takato14 or anybody,
Im not sure how to open SS-100 so as to access and remove wool damping behind the driver. I wonder if the outside grills can just be pryed off, but Id rather not try because am scared of permanently denting. And underneath the pads its not so clear how to open from that side unlike T30 and T50 where there were exposed screws and less tight fittings.

HI Philimon,

The outer part of the cups come off by rotating them.

See this post by MDR30: https://www.head-fi.org/threads/the-new-sansui-ss-100-thread.293113/post-11670363
and this photo of the innards by Tinkerer to help you guage : https://www.head-fi.org/threads/the-new-sansui-ss-100-thread.293113/post-11670363

I agree with MDR30 that some flat rubber (i think i used a resistance band) helps with grip, there may be a hint of dry glue to crack when opening it. The main things to watch out for are; 1) not denting the metal grilles, 2) the entire earcup is suspended by a rubber ring fixed at a handful of points, try not to rotate the cup against the frame, but hold both sides of the cup (i.e. not impart any force to these rubber suspension points, just twist the cup open like a bottle lid by gripping both sides. taking your large earpads off will help)

 

[Philimon]

taking your large earpads off will help

Thanks so much Kabeer!

I ordered a couple more of the same pads but in slightly smaller dimensions. in transit

 

[Philimon]

Info pulled from SS-100 thread.:

Another interesting note is this already has 4 conductors in the main cable and can be converted to balanced very easily without recabling the whole thing. Just terminate it in a male 4 pin XLR and you can plug in the 4 pin to new balanced amps or make/buy an adapter for dual 3 pin xlr balanced amps and still have a 1/4 stereo to 4 pin XLR female to play unbalanced on anything else.

Opening the cups: the grills are sort of bayonet mounted, with some glue. If you put your palm flat on the grill, press gently and move anti clockwise they should come off. A flat piece of rubber (from a bicycle tube) helps transfer the force.

… unsure if they are describing same thing but we’ll see …

It's the grill and the upper half of the plastic housing. The plastic is where all four of the attachment points are located.

They were first in production in 1975.

Original MSRP in Japan was 16,000 JPY, ~$133.50 USD in 1975. Factoring in inflation rates (2015), that's almost $600 USD in today's money. These were the second most expensive headphone in the world at the time, the first being KOSS's ESP/10, which was <FAR> higher in cost (100,000 JPY)