Orthodynamic Roundup
Oct 10, 2018 at 8:46 PM Post #25,906 of 27,137
That V1 seems a totally different thing entirely.
Last bunch of posts I read over there about V2 they are currently in the process of going through various iterations of drivers from the factory which are all tensioned differently from each ( plus maybe other things?) other to nail down the sound.
Especially the low end/
Low end and mids are apparently where they now need to be.
Will see what happens.
 
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Nov 12, 2018 at 2:52 AM Post #25,907 of 27,137
Well finally got annoyed enough with the stock "domino" 5 pin plug on these HOK80-2 to do a recable. I think I lost my crap-tastic adapter somewhere.
Stock form these in my opinion are over-damped a bit.
They sound decent stock but there is a lot more to be had with some effort.

The main reason I had these out for modding tonight was because yesterday I took the original model HOK80 ( V1 ) out for a walk.
Not bad...better than I remembered.
Then I threw on the impedance switch to high, the gain switch to high and bass boost on the portable amp seen in the picture ( it's a C&C XO2 @ 1 watt per channel )
Whoa.
I can't for the life of me recall what I did inside them except seal up the baffle holes where the tabs are, and some inner damping.
Since I had such great success with the Yamaha HP-50, plus other people's hearing and impressions to back me up on that mod scheme, I figured I would duplicate that in these HOK80-2.

No matter what * most times :) due to the opening process tabs are likely to break. These use 4 clip-tabs you need to pry back and then as ericj mentioned put some pennies in as spacers.
then work around until it comes out.
Inside that is a really goofy plastic ring that holds things in place stock. Tapered on the outside.
You really need to pay attention to this ring as it has 4 outer slots corresponding to the tabs, then one inner where it allows the cable to emerge from inside the ring and be clamped in place.
Since I went with some Furutech F35 fancy headphone cable I had to avoid wrapping the cable around the driver edges like stock, it was simply too thick to use with the ring like that

Replacing everything is really a total pain too as the ring needs to be kept in place as much as possible, plus it tends to move around during seating everything.

I did like the stock form =====but it really needs some serious power behind it and as I stated it seems stifled in the bass areas with the original grey wool damping puck.


So the HP-50A mod I used here involves getting 30D Sorbothane around the driver rears but here the driver holes go to the very edges so I had to put it on the baffle rear all around right at the driver edges.
Next to allow bass to throw better and not be immediately stifled and lessened, I put a disc spacer of the Hobbs Rough Silk quilt batting right on the driver rears.
Over top of that I put a disc of Arctic Cotton ( %100 cotton one ) for final damping and some reflecting as well.
I might swap that out for another spacer and %80 cotton batting, still testing.
Then simply reused the thin white spacer foam.


***Other tweaks include removing the stock plastic rear disc to convert them from closed to open ( it drops right out ),
and using a hobby knife to slice a bit of the cup edges where the headband pivots horizontally in ( it was catching those edges and clunking a bit )
and of course using some thin strips of Dynamat ( blue and silver version ) to secure the driver down fully ( stock form they are totally loose and simply held by the ring and cable wrap.)

For future reference the HOK80-2 driver polarity is
center tab on the driver is +,
outer edges are -.

Much thanks to wualta for that.


Coucou21.gif

HUGE difference. I though one time the bass boost was still on but nope. Anyhow getting used to this fist mod to see what I want to change if anything.
Not fun to open up.
Lettin' dat FURUTECH FHD-35 cable burn-in lol !



One thing I keep noticing is that many of my old mods that used the old traditional direct driver damping with heavier materials ( felts, quilt batting, wool pads etc )
always sounded...
welll... just ~not right.
Held back somewhat.
This spacer method really seems to work well for me.

I know this might be not common traditional thinking, these are damped in a sense though, just not immediate, and not as heavily smothered. When I get the same results across multiple items with that effect it tells me what I need to do ( HP-1 is done also like the HP-50A )
This tells me the bass needs more room to throw.
DSCF9963.JPG

^ 45/46 mm drivers , heck yeah look at those copper traces :) click for a nice closeup look !
You can see the broken outer edge of the baffle right at one of the tabs, almost unavoidable.

DSCF9965.JPGDSCF9966.JPG

^ that darned ring see the outer notches to line up with the slot on the press tabs, and also the small inner side single notch to line up with the cable exit.

DSCF9969.JPG
First and hopefully last mod result.
Neutrik 6.3 trs, FHD-35 cable, softy 3rd party HD25 pads that need no taping they snung tight right over the baffle edges.


ONGOING... isn't it always.
BTW if this page hits page 5 again I will be mad.
 

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Nov 12, 2018 at 4:04 AM Post #25,908 of 27,137
Can't seem to get the orange tinge out of the pics at this moment, lighting is sub-optimal.
Sorry about the not so great shot.
Anyhow another fast thing here.
TDS-16 larger ones in stock form, I swapped on some AKG K518 aftermarket pads that have the fabric backing layer on the inside.
This seems to help a bit with top ends.
Finding them though is a real chore as images on ebay sellers are deceptive.

These larger ones have a bigger driver than the smaller "Smela" ( btw that designation is only good for forum I.D., not for buying... things are all over the place so many factories.)

Notice that strain relief and cable.
Stock.
These sound different than the other variants. It's quite crazy the sonic variations between Soviet era stuff.
Even in the TDS-15 I have 3 different sounds.
I was reading over at the Russian forums about that and someone was saying that not only between various factories, but also between times of the month due to needing to make quotas.
=Earlier in the month more care was taken supposedly . Good luck figuring out the dates of each though if that is even true, unless there are user-manual pictures.
DSCF9970.JPG

Next up I might do the Pro30 open back mod. That one has been on the list for years.
 
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Nov 12, 2018 at 5:55 AM Post #25,909 of 27,137
Fast update on the HOK80-2 mod.
Sorbothane can be good at increasing clarity etc, inreasing efficiency by a few db and tightening things up, but in this case the driver is fully capable as-is and it pushed things just slightly over the top.

So a fast 5 minute opening and tweak.
-removed all Sorbothane,
-used 2 rough silk batting disks on each driver for more spacer depths ( this must have freed the driver even more in additon to the Arctic Material swap below ),
-dropped from %100% Arctic Cotton batting outer damper down to %80 which is slightly more porous ( held up to the light )

So pretty basic mod overall but this thing sounds crazily good now, and certainly sounds far from basic. ghz_01.gif
Thumping chunky bass even. No need for bass boost at all ( but don't expect to drive these with a substandard amp or phone that's for sure ).

Details are still present none that are shrill though now.
Everything is perfect.
Perfect.
"Sonorous" maybe?
Something I could sit back with for hours and lose myself in.
Wow.kabur.gif
Good thing I have a spare.

I had better slap myself because I must be dreaming here.
 

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Nov 12, 2018 at 6:26 PM Post #25,911 of 27,137
I recall that mod you did.
No idea what is going on here though.
I know you always use good cable, and your amp is really good so...
Only thing I can think of is that the space in the cups was too big to pressurize? But since these are opened up now that doesn't make sense. ( or was it too large a space with too little breathing? not likely either since the cans you used are perimeter vented I think. )
Did those have anything on the baffle front except for the driver hole, like tuning ports covered by white paper damping?
Maybe it is because I used that stock ring that ended up forming a type of chamber-damping?
The SFI stuff I did using a style of chamber-damping really responded well that way also and really brought up the low end a ot..

As I mentioned I use the hi gain, hi impedance toggles on that test amp.
Without bass boost things are good enough now where if I DO put bass boost on it does tend to get pretty heavy so definitely good for a bass fix, can be right at the edge of interefering even. At least for what I prefer in this particular presentation.
It's obviously improved vs stock just listening normally.

Who knows.
Odd stuff .
 
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Nov 12, 2018 at 11:13 PM Post #25,912 of 27,137
Wow, I haven't checked in on here in a while, but good to see Nick still fighting the good fight.
 
Nov 15, 2018 at 11:45 AM Post #25,913 of 27,137
Nick, surprised to know that removing the sorbothane was part of the path forward. I added some on the yammy HP-1, I think inspired by your experimentation, and haven't wanted to change much in the last year. Added a sprinkle in a AKG-K340s that took forever to tune to my liking as well. Without measurements it's obviously all subjective phenomenon - but I've been happy with my experience so far with using it in tuning. Big test I think would be taming the frame on the PMB-100. I've got to do a restoration on mine, it always sounded good but a wee rattle existed that I never made a priority to figure out. Probably time to dig it out from the land of banished wierdo-phones now that the days are shorert.
 
Nov 15, 2018 at 8:02 PM Post #25,914 of 27,137
Armaegis: Nice to see you pop back in. Did you see the recent post in the T50rp Incremental Mods thread someone was wanting to throw drivers into a V-moda :)

JadeEast:

Oh excellent I really appreciate that feedback on the Yamahas.
PLEASE post any ideas about tackling those PMB of yours.

I was really surprised at having to remove it, especially ALL of it.
What's there on those HOK already seemed near perfect somehow since I did still need to damp the rears somewhat..
With Sorb slight fatigue only kicked in after a longer listening session with various test tracks. Kinda like a feeling of slightly dulled-off sore and affected ears, so no good for long term.
Usually iso/orthos can take everything you can give them with the stuff.

I too have found it indispensible in the Yamaha things = especially the HP-50A mod! which luckily also translates near-identically to the bigger YH/HP-1 =
It really tightens up the otherwise looser bass into something where one ( me anyhow ) can more easily distinguish the note edges to follow individual basslines moreso.
Plus the clarity/transparency it brings to be able to do that.


Currently toying with a YHD-1
just to see how various mod materials and combinations affect those and just how the drivers handle modding in general compared to YHD-2/YHE-50's due to similar size.
All manner of damping variations on the YHD-1.
So far the two strips of Sorb alone seem to have done %90 of the job bonkers.gif and I am now having to really back off some of the damping pad materials slowly.

1- First damping setup was some Arctic Cotton type %80 cotton batting with a disc of the Hobbs Rough Silk below that on the driver to let it throw a bit better, maybe not enough cup-space to avoid being overly compressed, not that great.

2- Trying only an %80 cotton disc seemed to cut back the air too much and get pushed over the line on trebles.
Detailing was great just seemed smothered and lacking depth, sort of a detailed flat-wall effect.
Spaciousness was kept decent but that was a no-go for everything else.

3- Next up rear %80 cotton damping disc that cut out and exposed the 9 inner holes to fly wide open. Still too much fatigue, bass was bigger, details throughout the better depth slightly better.

4- Full main inner holes strip ( 3 holes wide across entire driver ) covered by %80 cotton. Hobbs Rough Silk perfectly cut out around that, bit better.

5- Square of %80 cotton covering the 9 inner holes. Hobbs Rough Silk perfectly cut out around that. Much better with noticably less driver constraint( this is good ), depth of detailing same as above but still tiny fatigue.

So further options are to see if the special detailing drops off, or is preserved at this level with just using :
= Rough Silk damping disc only.
= Arctic Bamboo ( thinner than the %80 cotton and more porous )

I simply don't wish to arrive at that open back syndrome where stuff drops away too early and cannot be followed outwards, plus loses the something special it has at this point.
So far that "special"seems maintained at the level needed.


TOO LONG / DIDN"T READ:

I've personally found Sorb necessary on Yamaha HP-50a and YH/HP-1 mods to fix the looser bass presentation.
YHD-1 trials slowly now getting nailed down.
Sorb does $%90 of the job just tackling preservation of special sonics without smothering things or fatigue.



Sorry to blab on.

BTW I really want to tackle the Pro30 open back mod.
I think that looks much nicer than stock.
 
Nov 23, 2018 at 10:39 AM Post #25,915 of 27,137
Armaegis: Nice to see you pop back in. Did you see the recent post in the T50rp Incremental Mods thread someone was wanting to throw drivers into a V-moda :)

JadeEast:

Oh excellent I really appreciate that feedback on the Yamahas.
PLEASE post any ideas about tackling those PMB of yours.

I was really surprised at having to remove it, especially ALL of it.
What's there on those HOK already seemed near perfect somehow since I did still need to damp the rears somewhat..
With Sorb slight fatigue only kicked in after a longer listening session with various test tracks. Kinda like a feeling of slightly dulled-off sore and affected ears, so no good for long term.
Usually iso/orthos can take everything you can give them with the stuff.

I too have found it indispensible in the Yamaha things = especially the HP-50A mod! which luckily also translates near-identically to the bigger YH/HP-1 =
It really tightens up the otherwise looser bass into something where one ( me anyhow ) can more easily distinguish the note edges to follow individual basslines moreso.
Plus the clarity/transparency it brings to be able to do that.


Currently toying with a YHD-1
just to see how various mod materials and combinations affect those and just how the drivers handle modding in general compared to YHD-2/YHE-50's due to similar size.
All manner of damping variations on the YHD-1.
So far the two strips of Sorb alone seem to have done %90 of the job and I am now having to really back off some of the damping pad materials slowly.

1- First damping setup was some Arctic Cotton type %80 cotton batting with a disc of the Hobbs Rough Silk below that on the driver to let it throw a bit better, maybe not enough cup-space to avoid being overly compressed, not that great.

2- Trying only an %80 cotton disc seemed to cut back the air too much and get pushed over the line on trebles.
Detailing was great just seemed smothered and lacking depth, sort of a detailed flat-wall effect.
Spaciousness was kept decent but that was a no-go for everything else.

3- Next up rear %80 cotton damping disc that cut out and exposed the 9 inner holes to fly wide open. Still too much fatigue, bass was bigger, details throughout the better depth slightly better.

4- Full main inner holes strip ( 3 holes wide across entire driver ) covered by %80 cotton. Hobbs Rough Silk perfectly cut out around that, bit better.

5- Square of %80 cotton covering the 9 inner holes. Hobbs Rough Silk perfectly cut out around that. Much better with noticably less driver constraint( this is good ), depth of detailing same as above but still tiny fatigue.

So further options are to see if the special detailing drops off, or is preserved at this level with just using :
= Rough Silk damping disc only.
= Arctic Bamboo ( thinner than the %80 cotton and more porous )

I simply don't wish to arrive at that open back syndrome where stuff drops away too early and cannot be followed outwards, plus loses the something special it has at this point.
So far that "special"seems maintained at the level needed.


TOO LONG / DIDN"T READ:

I've personally found Sorb necessary on Yamaha HP-50a and YH/HP-1 mods to fix the looser bass presentation.
YHD-1 trials slowly now getting nailed down.
Sorb does $%90 of the job just tackling preservation of special sonics without smothering things or fatigue.



Sorry to blab on.

BTW I really want to tackle the Pro30 open back mod.
I think that looks much nicer than stock.
 
Nov 23, 2018 at 10:49 AM Post #25,916 of 27,137
"Sorb does $%90 of the job just tackling preservation of special sonics without smothering things or fatigue."

Seems to line up with what I hear on the HP1. Took out the vent felt when I put in the ring of sorb on the back. I should crack them open and peak at what the current set up is in there. I know I pulled out any cotton that was in there and replaced it with synthetic. I've seen the cotton not age so well and densify in some of the experiments.

I've seen mention elsewhere of some experiments or success with adding fazor type treatments to some oaths. It's always struck me that the acoustic space on the front needs some attention too, but never really got far in my experiments. Would love to hear of any front of driver treatment successes.
 
Nov 24, 2018 at 12:29 AM Post #25,917 of 27,137
Armaegis: Nice to see you pop back in. Did you see the recent post in the T50rp Incremental Mods thread someone was wanting to throw drivers into a V-moda :)

Oh yeah, he messaged me a while back. I didn't have any spare drivers to send him though.
 
Dec 17, 2018 at 3:06 AM Post #25,919 of 27,137
HA! Well that's definitely a good one to get again, plus you know them well.
Strangely I have seen them at about half price these days from what they used to go for.
 
Dec 17, 2018 at 8:18 PM Post #25,920 of 27,137
I'm not even sure what the market for the old orthos is like these days. I remember years ago when I used to get all these messages from guys in eastern Europe asking if I'd sell them my headphones... it was an odd time, though good for sellers.
 

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