[inthere]

 
 
So an update on this sorbothane mod:
 
Added clarity because I took out the foam rings BUT soundstage closed up a bit and things are a lot more intimate now

How did you do the Sorbothane ? I did little squares on my HE-400's on the back of the cup and it helped out a lot. Yes I know open vs. closed and I don't know if you can get to behind the driver was just curious.

 
 I'm sorry, I REALLY want to take pics but I have the pads back on securely and I'm scared I won't be able to do it again. In the pic you see the white holes? You have 3 together on the top and two with a little distance between them on the bottom. There are 3 gaps with the two holes between them. I cut up rectangular pieces of peel-off-adhesive sorbothane and put 3 on each side.
 
They were quite thick sorbothane discs before I cut them up:
 
https://www.amazon.co.uk/gp/product/B00ZADBDYE/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1
 
Now a warning; this mod isn't for everyone. Those that like just removing the rings for that tuning probably won't like this one, because it adds bass, even though the bass is tighter. But it removes ALL of the ringing and harshness that you get from removing the rings alone. Also the soundstage is noticeably smaller. The pads are HELL to get back on and a crap shoot imo.
 
I now *think* I prefer this tuning to the stock tuning, but I was quite satisfied with the stock tuning until I read all the negative comments, lol. Not at all saying the comments were wrong, it's just I guess I'm just amazingly subjective and I couldn't get the criticisms out of my head when I was listening, if that makes any sense.

 

[Traveller]

 

That's weird. Yours looks like it does not have foam behind the driver cloth cover. I can see the plastic cap frame.

​I came across this post in the K812 thread:
Quote:

 


There are some interesting pictures of the insides of the K812 from the russian headphone forum. Actually plenty of things to try to improve by modding, especially that strange grid with 3 opened holes and 2 closed. The guy replaced the original acoustic fabric with some with less air-resistence and claims that there are some big improvements. 

While there's still no sign of the foam-layer you mentioned,@Beagle I was amazed to see that 2/5 panel-cover as part of the plastic frame...

 
What on Earth is AKG doing here? @Nomax - any ideas?
 

 

 

[Beagle]

   
While there's still no sign of the foam-layer you mentioned,@Beagle 

 
Is this on the original or what the modder added?
 

 

[Traveller]

 

   
While there's still no sign of the foam-layer you mentioned,@Beagle 

 
Is this on the original or what the modder added?
 

​Mod as noted by Qazxsw80.

 

[Beagle]

I'm wondering then why I feel something soft and cushiony behind the screen covering the driver. I am going to have to go back in.

 

[FastAndClean]

 
​I came across this post in the K812 thread:
Quote:
While there's still no sign of the foam-layer you mentioned,@Beagle I was amazed to see that 2/5 panel-cover as part of the plastic frame...

 
What on Earth is AKG doing here? @Nomax - any ideas?
 

ultrasone type of schitt

 

[FastAndClean]

LOOK AT THAT PEACE OF TRUE BEAUTY
 

 

[inthere]

Well, I was about to rave about the sorbothane mod as being the greatest mod ever but as soon as I took it off my Lau/Holo Audio Spring system and took it portable on an iFi Nano things didn't sound quite so awesome................I will however say that the isolation/leakage has been taken up not one but two notches and can now compete with the top portable cans in that department. Also the clarity with the sorbothane on the sides instead of right on the driver like the foam was is notecably better.

I don't miss the foam at all because the highs are notably smoother and less sibilant than before, while at the same time having better clarity and imagery. The soundstage is smaller, but it was huge to begin with. Really sensational cans now imo, and I finally think I can actually recommend the mod. For a closed can, I think I'd recommend this modded one for $3000.

 

[buke9]

Well, I was about to rave about the sorbothane mod as being the greatest mod ever but as soon as I took it off my Lau/Holo Audio Spring system and took it portable on an iFi Nano things didn't sound quite so awesome................I will however say that the isolation/leakage has been taken up not one but two notches and can now compete with the top portable cans in that department. Also the clarity with the sorbothane on the sides instead of right on the driver like the foam was is notecably better.

I don't miss the foam at all because the highs are notably smoother and less sibilant than before, while at the same time having better clarity and imagery. The soundstage is smaller, but it was huge to begin with. Really sensational cans now imo, and I finally think I can actually recommend the mod. For a closed can, I think I'd recommend this modded one for $3000.

This sounds really promising. Is everything reversible?

 

[inthere]

Well, I was about to rave about the sorbothane mod as being the greatest mod ever but as soon as I took it off my Lau/Holo Audio Spring system and took it portable on an iFi Nano things didn't sound quite so awesome................I will however say that the isolation/leakage has been taken up not one but two notches and can now compete with the top portable cans in that department. Also the clarity with the sorbothane on the sides instead of right on the driver like the foam was is notecably better.

I don't miss the foam at all because the highs are notably smoother and less sibilant than before, while at the same time having better clarity and imagery. The soundstage is smaller, but it was huge to begin with. Really sensational cans now imo, and I finally think I can actually recommend the mod. For a closed can, I think I'd recommend this modded one for $3000.

This sounds really promising. Is everything reversible?

Technically yes but it's not easy, I had problems getting the pads to lock back into place. I think I got it the last time I tried, but I'm too scared to remove the pads and try it again for confirmation

 

[hoanguyen]

Any of you know if the sound of AKG K812 and AKG K872 are similar?  I have 812 but want to add 872 to my collection if their sound are distinguishable.
Thanks.
HN

 

[xxx1313]

The K872 is MUCH darker sounding than the K812. Even after removing the foam rings, the K872 is rather neutral sounding with some added bass response, while the K812 is one of the brightest sounding headphones I know (even though the bass quantity does not lack for sure). The K872 has no sibilance, while the K812 is very sibilant with its 6kHz peak. The K872 is a bit more laid-back compared to the K812, which is more in the face. Both have slightly recessed mids in my opinion, even though the mids are quite different. Overall, even though they share some similarities, there are significant differences. So you could justify owning both, I think.  I would call the K872 ("defoamed" of course) to be a better, more neutral headphone than the K812 (at least with solid-state gear). Also its seal is perfect. However, I do not like the stock version of the K872, which is too dark and with rather impure bass.

 

[Traveller]

Originally Posted by Traveller /img/forum/go_quote.gif
 
Nomax

...Yes less Bass,but it has more then K812. Harman was wanting a very BASS HEAVY SOUNDSIGNATURE from Vienna for the US.Homemarket. Give it out Rings.....the Highs and Mids will be fresh and sounds much much more open.....or let it in ....you will have a muffled Soundsignature with very much bass...

 

Beagle /img/forum/go_quote.gif... It does not improve the sound in absolute terms. You get more perceived clarity but you also get glare and some harshness. The rings are a compromise to try and mask what seems to be a slight resonance in the diaphragm, possibly ... I removed them and put them back in because IMO the increased glare overshadowed a slight increase in perceived clarity...

 

Traveller /img/forum/go_quote.gif [IMHO] The ultimate test in the latter case is to put in roughly the same number of hours with and without the tweak. Only then can you truly be sure of the benefit / drawback of the changes... !

 
... I will follow my own suggestion and now listen to the K872s without the rings for at least ~30hrs...
 
Thin dampner (typical grey foam)...

 

 
So now that I've put enough hours I can confirm that I prefer the sound WITHOUT the foam rings.
 
Not once have I been irritated, agitated or felt fatigued due to any potential HF issues while listening to the K872s for longer periods. I've read your opinions, I've seen @EvilKillaruna FR graph and clearly there's something going on in the upper ranges but for whatever reason, it does not bother me.
 
As for the LF (bass, mid-bass), I don't feel like the "modded" K872s are lacking. There's that "line" between bass properly represented vs. bloat / boomy characteristics. I'll be the first to admit sometimes I don't recognize what side of the line my setup is presenting - until it is attenuated or promoted in a pleasing, positive way. But there are extremes where I am certain where I stand. The Etymotic ER-4S do not present LF "realistically" regardless of the "neutral" FR graph. My 1MORE E1001s have a bloated LF (albeit in a fun-sounding way) - no way to miss it.
 
So while I didn't freak out over the presentation of the stock K872s I do find it more appealing without the rings. In the end, a question of taste and not so much a question of error in judgment on AKGs part. Those strongly against or for the mod are clearly very sensitive to HF peaks or to mild LF bloat. The best thing about the topic is that this "mod" is a very simple affair and everyone should give it a try!
 

 

[hoanguyen]

Thank you for the details.  I thought they have similar sound because I was told that 872 is the closed version of 812.  I have Audeze LCD=X and LCD-XC but never try to find out the difference between them.  I like them both thought.
HN

 

[xxx1313]

The AKGs are much more different than your Audezes are. Although the AKGs have the same driver (at least officially) and many of their qualities are similar, they are tuned differently.
 
Especially the stock version of the K872 is quite dark sounding, because Harman wanted to meet the average presumed "American" taste.