[chrismini]

Don't mean to disagree by I find electronic crossfeed indispensable especially with hard-panned music from the early days of stereo when engineers and producers were "pan-happy" putting instruments hard left and right like most Beatles recordings. In fact I leave my switch on 80% of the time. Yeah it makes center instruments including vocals a bit bass heavy. In fact I'm hanging onto my HeadRoom Micro amp just for that option. I always A-B any stereo music I listen to and most of the time I prefer crossfeed. But that's just me. 
 
My sorb modified HE-400's still continue to amaze. My warranty expired long ago anyway. For all you HiFiMAN owners I seriously recommend you give this a try. I can' imagine anyone regretting it. And invest in some AC conditioning, especially if you live in a multi-unit complex where your neighbors microwave, etc. is probably polluting your AC power. Light dimmer are horrible offenders as is every computer your neighbors use which is all of them.    
Peace

 

[Benny-x]

In the HiFiMAN HE-6 thread changing earpads is a common way of tuning the headphones for people. A lot of people like the added bass and impact of using leather earpads there, but most people need to apply some felt or something to the inside, cylindrical ring of the earpads to help attentuate some of the high frequencies/reflections the leather creates vs. the stock velour earpads. 
 
Recently, though, an owner used 2mm strips of self adhesive Sorb. in place of felt and claimed the results were astoundingly great. He went back to compare with felt after all the other owners said it was their material of choice for this application, but he found the sound not to be as good as the with the Sorb. 
 
I haven't tried either yet on mine, but it was a very interesting nod for Sorb. and another potentially great use for it. This also makes me think that Sorb. doesn't only help dissipate vibrational energy, but also sound frequencies and reflections. 

 

[edstrelow]

I have been applying the double thickness of electrical tape to the back of sorbothane to turn it into "constrained damping" operation on my Polk SDA1 loudspeakers.  This is my first target after checking this technique out with the SRXIII pro test phones.. They are large speakers, about 4 ft tall and 1 1/2 ft wide so there is a lot of space to cover with sorb. Still I have put a fair number of sorb pieces on the front under the grill.  Adding the tape to the back of the sorb acts like a force multiplier.  Whatever the sorb was doing, taping the back just makes it do more. 
 
For example I found the thin sound of an old ABBA recording ( a friend once said the girls sounded like crickets) to be much less thin and more dynamic with individual instruments jumping out more clearly and air between the singers and or instruments,  an improvement I have generally found with sorbed headphones.  
 
Also Sprach Tharathustra sounded very clean, detailed  and impressive in the loud passages which are often just a loud mashup of sound, and for the first time I felt the room shake in the climax of the introduction. This is pretty hard to do because the  room is fairly large, open to the rest of the house and on a concrete slab.  It was actually a bit frightening since I live about 1/2 mile from the San Andreas earthquake fault and any shaking of the house makes you nervous.  I suspect that what happens is that the sorb dampens mid and high frequencies more than deep bass so I was probably turning up the volume and getting more bass that way.
 
I read on the Sorbothane site that  you may need to go to 1 inch thick sorb to dampen down to 10 Hz.  It might be worth a try to get super clean bass.  Not so practical on headphones though. 

 

[richard51]

very interesting, but if possible Ed i would like to see  if possible a photo of your loudspeakers with the tape....

 
I would be pleased if the same results were given with the tape, and taken off my load of concrete 

 

[edstrelow]

  very interesting, but if possible Ed i would like to see  if possible a photo of your loudspeakers with the tape....

 
I would be pleased if the same results were given with the tape, and taken off my load of concrete 

 
Hard to say how it would compare with your set-up unless you try both.  You have, as I understand it, not only used a damping base under the speakers, but you have  added lots of additional mass.  Adding mass is an old-school technique for achieving the same results.  People have used sand in their speaker boxes and I have even heard of speakers mounted in concrete pipes, filled with sand.  My personal guess is that each would produce slightly different results. 
 
I use spikes under these speakers and fastened them rigidly to the wall to get rid of vibrational energy (well the fastening was originally done to stop them falling over in earthquakes.)   And the sorb still gives marked benefits and the taped sorb even more.
 
I have just obtained some 70 duro 1/2 inch thick sorb which I intend to apply to the speakers to see if these will provide and additional clean-up of the bass.  I would have bought 1 inch but couldn't find any. I will let you know how this works out. 
 
There is nothing particularly special about my application of taped sorb to the speakers.  I have j used self-stick sorb and/or 3M80 glue to stick pieces all over the front.  I would have preferred to do this inside the speakers but I am not about to open them up. 

 

[richard51]

thanks Ed i understand... I will wait for your impression of this 1/2 inche sorb....

 
p.s. the sorb. under my speakers and on top of it act clearly better with the load.... If i take off some part the sound is less spectacular, and less presence...I also have put  around the tweeter and the woofer self-stick sorb but i dont know how to apply tape without  inesthetic effect....

 Samething for the amplifier or the dac, if i take off the load  the sound is worse....

 

[edstrelow]

I continue to be impressed by the advantage gained by backing sorbothane with 2 strips of electrical tape. So far I have done it with the Stax SR007 and Lambda LNS and both are now at the very top of performance.  
 
I have been waiting to apply the 1/2 inch sorb to my speakers and possibly some headphones. However since this material is not self-stick I wanted to investigate what adhesive to use.  I have been using 3M80, with generally good results on phones, but it had some problem adhering to wood. So  I wanted to try something else and have been trying Shoe-goo, something recommended by another contributor.
 
The results were not too good because it just didn't hold to the sorb although it held well to the aluminum covers on my Stax SRXIII test phones. Upon checking with Sorbothane  http://www.sorbothane.com/Data/Sites/31/pdfs/data-sheets/103-Sorbothane-adhesive-recommendations.pdf    I saw that they recommended cleaning  sorb with alcohol before applying adhesives, so I did this but it made no difference.  In the photo you can see that some pieces of sorb came cleanly off the phones, with no sign of adhesive on the sorb.
 
So I am going back to 3M80.. It may be that it was my failure to clean the sorb that caused some of it to fail.  Sorbothane has a number of other recommended adhesives, such as Lord 7650.  This is quite expensive at $35/ 1/2 pint.
 
 

 

[Jaab]

I had used a silicone glue for my sorbothane, the brand is Permatex, can handle  -59°c to 204°c 

if you want to remove it just peel it!

 

[edstrelow]

I am currently enjoying the sound of my main speakers with about 15 square inches of 1/2 inch 70 duro sorbothane mounted on each front panel. There is a big increase in the clarity and dynamics and the bass is far less muddy. I am using 3M 80 adhesive which is holding the sorb to the speakers well, so far.

1/2 in thick sorbothane is the thickest I can find online and I am trying it after reading, on the Sorbothane site, that 1" thick sorb will dampen down to 10 Hz. I guess you could request a custom order of 1" from Sorbothane, but I suspect it would be expensive.

I have applied a variety of thicknesses of sorb to these speakers, but with this last lot I feel I am starting to get benefits similar to what I have been getting on my most successfully damped headphones. More accurate timbre, better transients and dynamics and now much increased clarity in the lower frequencies.

At one point I removed a piece of triangular 3x1 1/2. 1/4 inch thick sorb and you could clearly hear that removing the sorb made the sound go muddy. It is not always possible to determine immediately the effect of adding sorb, since the,adhesive may take many hours or even days to fully cure. However, removing sorb gives you an almost instantaneous means of comparison.

It may not be possible to compare 1/2 with other thicknesses as I have been able to do with my Stax SRX III phones, (by swapping over the front covers with different test materials) because 1/2 sorb will not easily bend around the curvature of these covers. But such direct comparisons are the best way to get accurate information.

 

[richard51]

Very interesting.... I have the same experience with the sorb. duro 70 on top, under, around the tweeter and woofer and inside the porthole, for some months already... Our experience are the same and also conclusions... I will add that putting sorbothane anywhere  on any and under any gear will enhance the sound... Powerstrip, amp,dac,battery, ANY gear, particularly headphone, and speakers....

 
 
I will say something else about my second experiment mods. : CRYSTALS.... I have now put colored quartz,amethyst, topaz, tourmaline,jade, agathe etc on all the possible location, from the  central breakers panel, to the secondary breakers of my audio room, the panamax, the wall outlet, the amp, speakers, dac, etc the effect was so astounding, then it  complete the sorb. effect with a stupendous sparkle  natural 3-d sound .... I can assure you that EMI is no secondary problem compare to vibrations and negative resonance in the gear...
 
I will only say one thing for the beginners here : buy a mid-fi very good systems , or a  used  hi-fi old one, place sorb. anywhere, and place the crystals species i had already named, at all possible location, listen and experiment, after that i promise you  will FORGET any pricey possible upgrade  for a long time (diminishing returns law)... It takes me finally 6 years to touch this goal, Edstrelow give me the first hint 4 years ago  with his sorb mod of Stax, the second solution i discover  accidentally with only one crystal quartz on the breakers in the beginning,5 months ago, and this was the final small step to heaven .... It is all i can say on this thread dedicated to sorb.   Best regards to all of you ...

 
 
P.S. One of my customer at my work place, advise by me, bought for 6 dollars all in all , one pink quartz crystal, one amethyst, one little chunk of tourmaline, and put  one  of them on the central  breaker, the other 2 around the out of the power strip for the amp. and dac,  After that he phone me excited and happy ....End of story..
i think that he will trust me now for the more " complicated" Sorb. mod.

 

 

[edstrelow]

It does say "other materials' in the heading to this thread.   I am curious about crystals.  Can you give us a link or two to the material you are using.
 
As regards the 1/2 sorbothane, basically I am saying it is quite effective on my speakers.   It may be an reasonable alternative to the concrete blocs you have been using on your speakers.  Without trying it I wouldn't want to say.   Of course while I did remove some thinner sorb, I am adding it to speakers that already have sorb on them so I am may be getting somewhat of a cumulative effect of all the the sorb combined.   I just don't see myself doing the sorb of specific comparisons with speakers that I am able to do with headphones, using the interchangeable covers on the Stax SRXIII.

 

[richard51]

 Thanks Ed, i dont want to cause annoyance with this  controversial subject in dogmatic crowd but if you are interested with it, it is  Ok...
 
I have been in the situation to try and order many specimens  to experiment with without  previous experience about crystals....
 
Here are some  preliminary rules i have etasblished with my experiments:
 
 
Firstly : you can put the  crystals peebles in some plastic bag, or wrap them with saran wrap and scotch tape them in place....
 
Secondly : For  the  crystals in one  bigger piece,  the pieces must not be too big (  you can use quartz crystals between 1 inches and 2 inches (+or -) but they are very effective also in small  peebles bags in place of one piece of rocks...
 
 
 Thirdly :
For the green , or red  tourmaline,(black tourmaline is good but less musical than the others colored tourmaline) topaz or amethyst,citrin,  you can use small peebles mixed, or not mixed ( you decide by experiment) in a small plasctic bag. Mixing 2 species of crystals make some sort of equilibrium and compensation, and i now mix 2 species often or buy them naturally bond...Quartz can be chemically bond with a chemical element like fluor for exemple : fluorite, or  fuse with another stone: amethyst quartz crystal, and it is always good....Only pure one kind of rock stone  amethyst ,topaz,etc will be good or some pack of little peebles  mixed or not mixed is also good...
 
 the colored or phantom quartz crystals or any quartz fused with other chemicals element is very good and better than only white quartz...White quartz are very powerful and can be too much harsh sound if use  downstream in your system... I will  divide the use of crystals in 2 location  classes  
 
 
 
 UPSTREAM :  White quartz crystal or better any colored  quartz mixed with tourmaline or any other species you want to experiment with(very powerful, perfect for cleaning the electrical line)
 
--  On the  central electrical panel of your house on the breaker implicated with your audiophile room..
-- on other breakers in the audio room or before it...
-- on the power cord of the power conditioner...Or on top of the power conditioner also...
-- ..................................of the amplifier.
-- ................................ of the dac 
-- on the power supply in and out.
-- on the wall outlet in your audio room where all audio is connected.
 
 
DIVIDING LINE :  power conditioner or power strip
 
 
  DOWNSTREAM :  phantom or ghost quartz green or red Tourmaline, topaz or amethysts, ruby, even jade, or agathe   (these crystals are more subtle and more musical than the white  quartz, because of that better place in downstream with interconnect etc)
 
--  Principally all interconnect between all pieces of gear,in and out. 
 
-- on top of the transformer of the amplifier, or on top of any transformer...
-- on the in and out of the battery of my dac...
-- On the power switch of the amplifier or pre-amp or of the dac etc, one little peeble  ( i use blutak for that)
-- in the rear port hole of my speakers, or inside it if no port hole, or on the speakers cable...
-- on the headphone out or in the cable, or inside the headphone ( i will try that with some peebles)
 
 
In general white quartz is better upstream....It is cheap and easy to buy... try only one on the breaker and enjoy...In the first day i try that...After that i dont hesitate to order all other specimens...The list of rocks i give here is not exhaustive, but you are more safe to try that  for a beginning... I have order lava rocks to try and mix with some other rocks, but i cannot recommand that because i have not listen to that actually.... All others name of rocks i speak about here are good choice to experiment with...I dont know for all the other possibilities ...
 
Imagine the number of locations possiblities in your system, (15, i think in mine), multiply that by 6, 7, or 8  different specimens of rocks at different possible places, the combinatorials  results are very big numbers , hence i dont know the  final optimal disposition... Plenty hours to play with these possiblities...
 
And i will say that,(at the risk of opinionated people mocking me) NO one rocks sound exactly the same in my systems, like no tubes sound the same, and act differently in different place, often this is subtle, often this is not subtle and very audible...the upgrading effect is not small, but remember that my system is sorbothanized , the listening of the many  experiments is easy with this sorbothanized. system...At the end the effect is 3-d imaging on a superior scale than with only the sorb.and a better dynamic all across the frequencies board...To obtain that each stone will act on his own, and complement the others stones, at the end of the road  an optimal equilibrium,   without coloration of the sound like with some tube,  but with  only a more natural timbre and soundstage... 
 
 
These are ONLY my temporary conclusions, BUT the change in sound were so evident and when rightly place so great in the speakers or headphones that this is not even comparable to the change of tubes in my Ember amplifier,( i dont use it now, i prefer my Sansui by a long margin) hence no small upgrade...You must experiment to discover the right materials at the right place in your system...If you dont use sorb. in all your gear the change will be less spectacular because sorb clean vibrations and make easy to listen  the sound effect resulting from the cleaning of EMI ...

 
Without consideration of price ALL audio products are plague by vibrations and EMI, i know now that mid-fi system can sound like, or almost like,  hi-fi system modulo sorb. and crystals... 
 
P.S. to answer the question where to buy? Simple Ebay auction  or  aliexpress, i bought all from china because it is inexpansive,and i choose the company that charge zero postal fees... There is good deals on the auction system... 

 

[oopeteroo]

I'm new to this but I heard the sorb mod is good on Mt220. So i want to try it out.
Which sorbothane to buy ? I'm guessing the size and thickness would affect the sound ? Would be cool if anyone could link me to one in amazon.Co.UK

 

[edstrelow]

I'm new to this but I heard the sorb mod is good on Mt220. So i want to try it out.
Which sorbothane to buy ? I'm guessing the size and thickness would affect the sound ? Would be cool if anyone could link me to one in amazon.Co.UK

I have not seen any report of using sorbothane on these phones, but my take on this topic is that most phones have problems getting rid of vibrational energy which degrades sound. The problem is only now being addressed by the use of new materials with better capability of changing mechanical energy to heat. Sorbothane, patented in 1982 is one of these, but there are others being tried. Sennheiser talks about a 'space age' material in its HD 800 headband ( and presumably in its new stat phone), Grado has a proprietary poycarbonate, and I am uncertain as to what B&W and Audioquest are using.

If you look over the last several pages of this thread you will see that I have tried to do systematic comparisons of various materials, size, shap, adhesive and the like. For the moment I am recommending 1/4 inch thick, self- stick, 70 duro ( a measurement of density) sorb cut into small pieces, say 1/2 to 1 inch dimensions. I have been getting it from the US on Ebay, but Amazon US may have some. I don't think Amazon UK has had any. Ebay and Amazon are generally much cheaper than audio shops, and some of the shops don't even know what duro they are selling. I was able to get a 4x4 inch sheet of 70 duro, self-stick ,1/4 inch for about $12.00 US.

More recently I have also been applying backing to the sorb, consisting of two thickness of electrical tape.

As to where to place it, I think you want to stick it inside the earcups, adjacent to the drivers,. This has the,advantage of keeping it out of sight. You can also try the outside surfaces and even rigid sections of the headband. All the damping in the,Sennheiser HD800 is apparently in the headband.

The self-stick sorb holds better over time and you may not hear properly what it is doing until an hour has passed from the time of application. But can be peeled off if you want to change or remove it.

I found this on US Amazon. Sorbothane Acoustic & Vibration Damping Film 70 Duro with 3M Adhesive Backing (0.25 x 6 x 12in)

Be the first to review this item Price: $43.95. This is a lot more than you need for one phone but you will find you can apply pieces all over the audio chain.

Hope this helps.

 

[richard51]

UPDATE:
 
Not only crystals of various kind ( especially amethyst, topaz,tourmaline,colored quartz or phantom quartz,or rutilated quartz, agathe, aventurine,citrine,ruby, etc) are one astounding upgrade in an  audio system, like all my experiment with a variety of them demonstrate to my ears, and not a light upgrade but a very great one indeed, (trust me!) but now i must say that my experiment with stones, 4 bags of them i purchase in a one dollar shop (aquarium section), stones from a river bed of various shapes and colors, and they made a surprizing upgrade in top of my many crystals... I put one bag of them on top of the Panamax power conditioner  (with the tourmaline crystals already there) where my amp is connected, and 2 bags of these stones under the bi-wiring posts of my cable's speakers (already crystallized with 2 species of crystals and sorbothanized) WOW i sense an immediate upgrade in 3-d clarity, without diminution of highs and bass....ALL THAT WITH A FOUR DOLLARS for 4 bags  of  various stones river bed ( i have put one last bag on top of the  central  electrical panel with the already there tourmaline and  white quartz)...It seems to me that the action of these stones are subtle all across the frequencies but no less discernible at the end than the crystals for cleaning EMI, hence at the end,contrary to tubes rolling for example, there is no more trade-off, only a total cleaning up of the image and sound (the imaging go to another level in my speakers but is also sensibly better in my He 400)... ...
 
You must remember that the location of crystals,and stones, and also their combination and mixing in your system is of prime importance for the final optimal results; so listen to, and make change, but listen to for some time between experiments... The combinatorial possibilities is way too much to wrote a ready made formula for all, so experimenting is your key...It is easy and for me it is like rolling tubes for a better satisfaction, but without the trade in and trade off in the frequencies and soundstage or imaging possiblities....Crystals and stones pilot your systems to his ultimate potential easily and better than tubes in a tube amp...It is an interesting fact to report that if your system is already hi-fi, without too much plaguing vibrations after the application of sorb., you will sense clearly the qualitative differential  effect of moving crystals to one place or another in your system...For  the dogmatic sceptic, who read my words, who have only  absolute opinions and zero experiment, for the one that would say to me : all your fuss  description is the result of some placebo effect, i only  dare to say clearly, viva placebo!

 
 

 Now my question is what price i must pay to upgrade my actual speakers, or Sansui amplifier to obtain the  same level of upgrade with a new better gear? With sorb. stones and crystals all that cost me is  some few bucks...But  without the sorbothane nor crystals nor stones solutions,perhaps thousands of dollars of new gear will do the upgrading job, i think so? Never mind! remember here the law of diminishing returns....
 
What is the better solution for most of us?  

 the answer is simple: Often it is not necessary to buy  new gear, except if you hate the one you  already have, it is necessary to buy sorb. crystals and stones first, to truly hears what you have already  perhaps like me for the first time... After that you will listen to music, and not to the sound ...This is my experience here, thanks to the initiator of this thread, contacting him was one of the great act of my lifetime, and after the meeting of my wife, and the discovery of great books,music is for me the  third part of my life... 
 
 
A word of caution:
 
I cannot assure to you that the results with these cheap stones will be for you what i describe them to be in my system, especially  if you dont have any sorb.,nor crystals already on your system,but i cannot imagine that you will not perceive some difference with only these stones...You can thank me after that experiment, because if crystals are less costly than sorbothane,for one canadian dollars each bag of stones, this upgrade is way across the roof in term of the ratio sound quality/money...
 
 
 
 

 
 
 
On top of the cable binding posts i have a sodalite quartz crystal+a chunk of  black tourmaline (glued there with some blutak) that greatly enhance it, touching the 4 cables there are the  stones river bed....