[MDR30]

One of the most interesting notions recently are the function of the thin paper on the back of the Grado drivers. There are ten holes behind the diaphragm, covered by this material. Bilavideo and others have discovered that the bass reproduction increases (on SR60) if this paper is removed. But does it affect the mid and treble response?
 
Apparently a few Grado/Alessandro models have some of the holes uncovered:
 
HF-2ne hole
Alessandro MS1: two holes
Magnum: three holes
GS1000: four holes
PS1000: four holes
 
Any other models?
 
Links:
 
http://www.head-fi.org/forum/thread/497440/buy-sr60i-or-sr80i/60
http://www.head-fi.org/forum/thread/497440/buy-sr60i-or-sr80i/90
 
This thin paper is fascinating! It's been used in front of and behind the diaphragm for ages. In some cases to dampen treble, in some to increase bass...
 
Theorists out there - enlighten us.

 

[nickchen]

Those links don't work...

 

[Bilavideo]

One of the most interesting notions recently are the function of the thin paper on the back of the Grado drivers. There are ten holes behind the diaphragm, covered by this material. Bilavideo and others have discovered that the bass reproduction increases (on SR60) if this paper is removed. But does it affect the mid and treble response?
 
Apparently a few Grado/Alessandro models have some of the holes uncovered:
 
HF-2ne hole
Alessandro MS1: two holes
Magnum: three holes
GS1000: four holes
PS1000: four holes
 
Any other models?
 
Links:
 
http://www.head-fi.org/forum/thread/497440/buy-sr60i-or-sr80i/60
http://www.head-fi.org/forum/thread/497440/buy-sr60i-or-sr80i/90
 
This thin paper is fascinating! It's been used in front of and behind the diaphragm for ages. In some cases to dampen treble, in some to increase bass...
 
Theorists out there - enlighten us.

 
This paper is routinely used on closed-back cans to allow more bass slam from the backwave.  The paper is a cheap substitute for the passive drivers on the old K240 Sextett.  You're getting bass reflex (recycled backwave) but you're getting it  slightly filtered.  It's not as useful on an open-air headphone (though it's slavishly repeated).  I found that the paper limited the open-air quality of the driver and that removing it dramatically increased the airflow.  The only downside is the sudden relevance of the air chamber and whatever it is made from.  If you have something like plastic, you'll get resonance off the plastic, which is why this mod should be accompanied by damping of the air chamber.  It's not an accident that Grado vents the driver more with wood and aluminum chambers than with plastic.  Damping with felt has been useful as a measure, short of woodying the back chamber, for getting more bass without also getting a canny echo off of plastic.
 

 

[TheMiddleSky]

Just an ordinary Woody Alessandro (Woody by Oery)
 

 
 

 

[harj]

 
Pictures of my PS1000's with JMoney v3 headband and black and silver silicone bands to protect the earcups. 

 

*Pictures taken with my iPhone so not the best of quality.

 [size=medium]

[/size]

 

 

 

[TheMiddleSky]

how you can get the that silicone? from jmoney or what?

 

[zer061zer0]

Anyone tried grado with cardas? Any good?

 

[les_garten]

Quote:

Anyone tried grado with cardas? Any good?

I would think that would be a good Combo from my experience with Cardas.

 

[zer061zer0]

Actually, I did try it before I thought it was quite amazing, but I need some opinions just to make sure that its not a placebo effect. However it have been a while since I last heard it, and after the relocation all my equipments are all scatter around.
 
Anyone who tried the cardas with grados, do post some opinions, it would greatly impact what I want to do with my grado next.

 

[EddieE]

[size=x-small]So let me ask this - I certainly agree that felting the chamber after the "hole punch" mod refines the sound, but if our end-game is a minimum of resonance might an evenly distributed decent thickness layer of something like dynamat, very carefully and precisely applied to the entire insides of the air chamber (except the air holes) be the best solution? [/size]
 
[size=x-small]I know some people dynamat the back plate of the driver magnet, but if the stuff is specially designed to kill resonance blitzing the whole chamber with the stuff might be even better than wood?[/size]
 
[size=x-small]If people think it'll work I'll go ahead and order some and play guinnea pig.[/size]
 
[size=x-small]P.S. Contrary to the post above, the MS1 has no holes opened up stock, neither does the SR125i and I assume all plastic chamber Grados for the reasons Bilavideo suggests.[/size]

 

[EddieE]

Harj!
 
You've got TWO PS1000s????? Greddy bugger!

 

[jagerj]

This is my pair of sr-225s. Was Given a set of black anodized 325 canisters which I modified slightly, removing the plastic liner and outer buttons. J$ V3 Headband.

 

[yashu]

I cut strips of electrical bundling tape, and put it on an older set of bowls.
 
I also carefully cut them to length to give just the right amount of low end punch, and a tad less bright. They sounded amazing when I auditioned them, and they sound even better now. I love the Grado design, meant so that they can be easily hand assembled. Even the ones made overseas still has that legacy in how many things you can do to them.
 
IF there is a way for me to use the old 325 barrels, I will find it, I like the classic look. I am angered that it is so hard to remove the headband from the gimbles because I want to put the actual leather band from the old ones on hrere, rather than this vinyl, however, I am not worried about any flaking, I can say that much!
 
 
If I do open them up, what character does poking the felt screen holes bring? I can practice on an older broken grado driver, but I need to know that this warrranty voider will give me positive results, and not accent more flaws.
 

 

 

[blueapple]

cloth gone, then...............

all 10, then.................

little bit of blue-tac on driver and sides, then..............

custom grills, 

nothing special i just wanted to see pics of my cans hehe!
FYI if i had it to do all over again i would.

 

[Bigrock2150]

One of my recent grado mods.
 
I have a website that sells grado cups but due to Head-fi rules I can't disclose my website name. 
 
Anyway...