[FullRangeMan]

Getting a headache with your can, try this cheap slip on cushion pad:
http://www.amazon.com/Replacement-Leatherette-Universal-Sennheiser-Beyerdynamic/dp/B00862522A

[FullRangeMan]

How a Orthodynamic/planar magnetic headphone driver works:
http://www.youtube.com/watch?v=3I2lyIQDC24
Text:
http://www.innerfidelity.com/content/how-planar-magnetic-headphones-work

[FullRangeMan]

How mods your stock Sennheiser HD580/600/650 to a more open grid and let the dust enter more easily:
http://apuresound.com/hdsennmod.html

[JohnR]

I removed the front foam from my 650's as an experiment and really preferred it put back. YMMV... I suppose I might try a more controlled experiment at some time but OTOH... if you like listening to what you have then listen... if not, maybe you just backed the wrong horse.

[dB Cooper]

I am thinking of adding some plast-i-clay to strategic spots inside my Senn 650s but I am reluctant because 1) they are so new and 2) housing resonances are already very well controlled in the 650 as the driver baffle is made of carbon fiber. Did it on my 555s with resulting improvement in clarity.

JohnR makes a good point…. you can alter almost anything but real improvements are hard to come by, especially if the designer of the product already had a good idea of what he was doing.

[FullRangeMan]

Interesting phones support, a bit short for full size headphones and its cable, it would be cheaper too:
http://www.amazon.com/FortuneCat-Headphones-Sennheiser-Skullycandy-Platronics/dp/B008F4YKCW/ref=pd_sim_e_55

[dB Cooper]

Had some spare time Thxgiving eve, so here's how I modified my Sennheiser HD650s with "plast-i-clay", á la instructions published many years ago by Frank van Alstine in his "Audio Basics" newsletter, "scaling" the recommendations there to headphone scale.

The first shot is just the stock cans.

The second shows the areas where I applied the "plast-i-clay". In the areas indicated by  the Orange arrows, I apply a thin coating, maybe 1/16" (maybe a wee bit thicker on the circular ring, that is where the energy from the driver gets transmitted into the surrounding baffle). A little goes a long way. The green arrows are "cavities" in the baffle; you can fill these flush with the surface. Resonances go there to die. In particular, the green arrows closest to the center are raised at the center and when filled, the plat-i-clay will have a basically triangular cross-section flush with the top and bottom edges. It is hard to see in my pics because of the head-on camera angle. Made some adjustments after taking the "modded" pic but you get the idea.

Do not get any plast-i-clay on any of the white silk or the black open cell foam near the center (indicated by red arrows) as these will affect the tuning. 

I found some dark gray, almost black, "Plastilina" brand clay at Michaels, a craft/artist supply store in my area. It blends in real well with the black finish inside the 650s and you would need a flashlight to notice it. Made it a little hard to see in the "modded" pic too (sorry).








And the sound?
The modded 'phones have an even "blacker" background than stock, impressive as resonances are quite well controlled in the stock 650. Clarity is improved, transients and reverb tails are clearer, and instruments' location in the "soundstage" is better defined. I am very impressed as the stock 650s are no slouch right out of the box.
 
These mods could be easily transposed to other cans with the caveat that you should be very judicious if working with sealed cans; too much will affect the tuning. With open back types where there is no "enclosure", this isn't really a problem. If anyone is interested in doing this, I recommend downloading Vol 1 No. 1 of the "Audio Basics" newsletter from the Audio by Van Alstine" website. Substitute the word "headphones" for "speakers (although it has helped every set of speakers I have tried it on; you might want to try that too!)

If you try it, you are of course responsible for getting your cans apart, modded, and back together without destroying them. dB Cooper assumes no liability yada yada yada.

[FullRangeMan]

Thanks dBCooper, very instrutive, a image worth a thousands words.
Just drop on it, a ''genuine'' replacement cable for Sennheiser HD500/600 and HD-series for only 25 dolares.
Said manufactured by Sennheiser:
http://www.amazon.com/Replacement-Cable-SENNHEISER-Headphones-HD650/dp/B0028PGXRE/ref=pd_rhf_se_s_cp_2_AG5K?ie=UTF8&refRID=0HMH7R7VXF1CF9JX47A9
Unfortunately the lenght cable is the usual 3 meters, too long;
After around 1 metter a cable may suffer the antennae effect.

[dB Cooper]

I'm gonna have to risk it; I'm not willing to be stuck one meter from my headphone amp. If this was a big problem speakers would have it even worse.

Really amazed by the improvement in everything I have treated with this material (mostly speakers). Kudos to Frank Van Alstine for turning me on to it years ago. Particularly surprised here as the HD650 is one of the more resonance-free cans I have heard. The plasticine makes it sound like a whole layer of 'mud' has vanished.

[FullRangeMan]

I wonder if the bulk caulk sometimes called dum dum(butyl rubber) or similar product had a better sound quality in this job than the plast-i-clay you mention??
http://3mcollision.com/3m-strip-calk-08578-black.html
or this
http://www.elastobor.com.br/Massa-Calafetar-Filete-Cinza-350g--detalhes-16468-508.html

[FullRangeMan]

Just see Sennheiser released 4pins XLR balanced cable for the HD800.
Price are more expesive than most aftermarket cables;
http://en-us.sennheiser.com/dynamic-headphones-high-end-around-ear-hd-800

[dB Cooper]

I wonder if the bulk caulk sometimes called dum dum(butyl rubber) or similar product had a better sound quality in this job than the plast-i-clay you mention??
http://3mcollision.com/3m-strip-calk-08578-black.html
or this
http://www.elastobor.com.br/Massa-Calafetar-Filete-Cinza-350g--detalhes-16468-508.html

Only way to know is to try it. As described in the AVA newsletter, a good test is to make a ball out of it and drop it on a hard surface. If it bounces, it's no good. Rubber caulk also would likely lack plasticlay's easy removability. You could try it but plasticlay meets all requirements for the material and is a known quantity (it has improved everything I have used it on). I think Frank said B&W tried a similar material and he didn't think it worked as well.

[dB Cooper]

Just see Sennheiser releaseD 4pins XLR balanced cable for the HD800.
Price are more expesive than most aftermarket cables;
http://en-us.sennheiser.com/dynamic-headphones-high-end-around-ear-hd-800

Holy sh**, $380 for a headphone cable. That's more than I paid for my HD650s. Puh-LEEZ.

[Guy 13]

Hi dB Cooper and all Audio Circle members.
Again I must say and ask:
Is that up-grade really worth (Every penny of) the 380 USD ?
By how many % will it improve the sound quality?
1% or 5% or maybe 10% ? ? ?
They are asking for that up-grade more than 25% of the price of the HD-800.
Well, if you have the money, why not.
For me, even if I had the money, I would not buy it,
because I think it's unreasonnable.
But again, that's me.

Guy 13

[djbnh]

Thanks dBCooper, very instrutive, a image worth a thousands words.
Just drop on it, a ''genuine'' replacement cable for Sennheiser HD500/600 and HD-series for only 25 dolares.
Said manufactured by Sennheiser:
http://www.amazon.com/Replacement-Cable-SENNHEISER-Headphones-HD650/dp/B0028PGXRE/ref=pd_rhf_se_s_cp_2_AG5K?ie=UTF8&refRID=0HMH7R7VXF1CF9JX47A9
Unfortunately the lenght cable is the usual 3 meters, too long;
After around 1 metter a cable may suffer the antennae effect.

Senn sells it even less expensively @$12.32, I didn't check shipping costs: http://en-us.sennheiser.com/cable-hd-650.

[FullRangeMan]

Only way to know is to try it. As described in the AVA newsletter, a good test is to make a ball out of it and drop it on a hard surface. If it bounces, it's no good. Rubber caulk also would likely lack plasticlay's easy removability. You could try it but plasticlay meets all requirements for the material and is a known quantity (it has improved everything I have used it on). I think Frank said B&W tried a similar material and he didn't think it worked as well.

Thanks for clarify; 

[FullRangeMan]

Seems this balanced Senn HD800 cable use the well know Senn cable which is some times replaced by users.
A much more cheaper option are cut the 63mm banana plug and solder a suited XLR plug.

[MikeCTM2]

Hi.  Just got my Sennheiser Momentums last week.  Excellent stuff.    I'd like to get a longer cable.  Is this possible ?   I have been searching.  Have found nothing yet.

Insight Appreciated !

[dB Cooper]

Seems this balanced Senn HD800 cable use the well know Senn cable which is some times replaced by users.
A much more cheaper option are cut the 63mm banana plug and solder a suited XLR plug.

Not sure anyone spending $1500 for a set of cans would be "thrift minded" enough to hack the stock cable. I would either just drop the $380 or leave it the heck alone and spend the 380 on, say, a lot of good music.My feeling is that if the stock cable wasn't satisfactory, those 'phones wouldn't have had the impact they have had. I find Frank Van Alstine's argument that if your cable changes the sound of your amp, that means your amp is sensitive to load variations and that is not good, persuasive.

[Guy 13]

Not sure anyone spending $1500 for a set of cans would be "thrift minded" enough to hack the stock cable. I would either just drop the $380 or leave it the heck alone and spend the 380 on, say, a lot of good music.My feeling is that if the stock cable wasn't satisfactory, those 'phones wouldn't have had the impact they have had. I find Frank Van Alstine's argument that if your cable changes the sound of your amp, that means your amp is sensitive to load variations and that is not good, persuasive.

Hi dB Cooper and all Audio Circle members.
I agree 200% with you.

Guy 13