[karthikrr]

I've been a stalker at head-fi for a while now. Had a Grado SR60 from about 5-6 years ago that started giving me problems, so hung out a bit here and finally decided to buy the SR80i and a FiiO E10. Was quite happy with it, until I replaced the comfies with bowls, which made it a lil too bright for me. Thats when I opened up the mod thread, and after getting through some 30 pages, I went ahead and dug out my old SR60 to experiment.
 
The problem that the SR60 had, which prompted me to buy the 80i (just needed an excuse really), was simply a plug that had the right channel wire come off, and a lot of 'grattling'. I soldered a new plug and then set about opening up the driver assembly to figure out what to do with the grattling. Turns out it was just a lot of hair and dirt that had managed to find its way in over the years. Once I got the mesh off, I spent about 15 minutes blowing from the side to get the hair to stick out and then pull it out. Finally cleared it up enough to get rid of the LF distortions.
 
Of course, I couldn't stop here, so went ahead and vented the damn thing. I saw a few posts saying four is the sweet spot, but I got greedy and did all 10. Observations as under:
 
General Comment: I find too much mid-bass and a very muddled sound. The clarity that Grados are known for is gone. I tried experimenting with different pads, and this is where Im a little confused:
 
1) New comfies from the SR80i: The modded SR60 sounds like crap, I hear bass, I hear treble, the rest is just some background noise.
 
2) New bowls: Much better than the comfies, it sounds ok, but just not that impressive. Actually, sounds boring!
 
3) Bowls reversed (not inside out): Brilliant bass, but the trebles are also heightened and some frequencies are just too grating to bear. Im gonna guess this is what sibilance means. For example, theres a track with some whistling, and it physically hurt to hear that section!
 
4) Bowls inside out: Pretty similar to the reversed bowls, though it didn't seem as jarring as the reversed bowls. Im gonna chalk that up to placebo and say its the same.
 
5) OLD FLATTENED COMFIES: I put that in caps because these are the original comfies from the SR60 that are literally falling apart in my fingers. They are flattened so much that they seem 30% wider than the new comfies. They are also quarter modded, though the circle is now a weird shape with slits because its just in that bad a condition now. The bass is SUPER pronounced with these, but there is still a bit too much HF. And then I tried these WITHOUT the caps, just open in the back, me holding the drivers up to my ears, without the headband ... WOOOOOOOOOOOOOOOOOOAH, this was like having two tiny subwoofers around my head! And the treble was gone as well, sounded perfect. And nope, none of the other pad configurations was the same, with the open drivers.
 
Questions:
 
1) Will ripping out the grating/mesh in the back cup/enclosure help preserve this sound? There is a HUGE difference to just the drivers and with the cups back on. If you haven't tried listening to just the drivers with a foam pad around it, TRY IT, its crazy!
 
2) I don't know where I read this, but I seem to recall somebody suggesting the way to seal the vent holes is to stick a piece of used dryer cloth with tape? Is that the generally accepted way to reverse the mod? I want to reduce the bass creeping up into the mids, need it to be a tad tighter.
 
3) Will adding the damping mods with felt liner cut down the crazy HF? If not, what purpose do these serve?
 
4) Any other thoughts and suggestions, or questions? The SR60 is just a guinea pig right now, so if theres any ideas for experiments that will not destroy the drivers, Im listening.
 
Thanks!

 

[wje]

I think to cure some of your bass issues as a result of opening all 10 holes, you could cover up about 6 of them and see what the results are.  Last year, I used felt or muslin cloth (as recommended by Chris).  However, being a modder of the Fostex T50RP, led me over to micropore tape.  It is a paper-based tape that is in the first aid section at your local drug store.  It is sold on rolls like Scotch tape.  The micropore will or should have enough openings in the material to allow enough needed bass to pass through, without congesting the driver.  It's a cheap product - $4.00 or $5.00, tops.  Certainly, much easier that scouring the aisles of a fabric store trying to find the right product to work on covering the holes.
 
The rear "mesh" really won't have a big impact either way in regards to the frequency response.  The Grados that go up in range a bit, offer a metal mesh as opposed to a stamped plastic mesh.  Some people have performed the mod by using a Dremel tool to cut out the old plastic mesh and glue in some new metal mesh.
 
One of the mods that was known to have a bit of an impact on controlling some of the treble was using a small piece of the Dynamat rubber / butyl (black portion).  You remove it from the foil section and make a ball about 1/2" in diameter.  Carefully, press the ball into place and slightly flatten on the back of the rear driver (flat silver or black portion) ----- BUT, be careful not to cover the two holes that are clearly visible on the outer edge of the circle flat area.
 
Good luck to you!  You'll be surprised how some simple mods make some nice strides at improving, or changing the Grado sound a bit.

 

[karthikrr]

Didn't know what it was called, but I do know the tape you talk about! Will go buy some tomorrow and experiment with different vent configurations... Thanks for the tip!!!
 
I didn't expect the mesh/grill to have any effect, but maybe the cup itself does? It just sounds completely different when I'm holding up the open drivers to my ears. I also tried ripping apart the plastic grill and button, did a terrible job of it, but enough to know that opening up the grill isn't going to help. Thus the conclusion that the end cup itself is affecting the sound. Trying to think of alternatives to use in the back, see how the sound changes. Will report back if I notice anything interesting.
 
With the dynamat mod, all that is being done is weighing down the magnet, right? Kinda like dampening it, which seems intuitively likely to cut down the top end a bit? This leads me to wonder if the perceived problem of low bass impact on the Grados is not so much missing bass, but just that its overwhelmed by the highs... Maybe I'll try covering up all the holes and just damping the magnet, see what that does.
 
I also just bought a pair of used 325i drivers from LCfiner here. If I understand correctly, the drivers are attached to a longer (than SR60/80i) plastic sleeve, over which one simply mounts whatever casing, whether it be wood or aluminum. Is this right?
 
I was planning to just stick them in the SR60 cup, but a few threads seem to suggest that its going to sound more like a 125i than a 325i if I do that. Does anybody here have specs for the 325i's enclosure?

 

[wje]

Quote:

Didn't know what it was called, but I do know the tape you talk about! Will go buy some tomorrow and experiment with different vent configurations... Thanks for the tip!!!
 
I didn't expect the mesh/grill to have any effect, but maybe the cup itself does? It just sounds completely different when I'm holding up the open drivers to my ears. I also tried ripping apart the plastic grill and button, did a terrible job of it, but enough to know that opening up the grill isn't going to help. Thus the conclusion that the end cup itself is affecting the sound. Trying to think of alternatives to use in the back, see how the sound changes. Will report back if I notice anything interesting.
 
With the dynamat mod, all that is being done is weighing down the magnet, right? Kinda like dampening it, which seems intuitively likely to cut down the top end a bit? This leads me to wonder if the perceived problem of low bass impact on the Grados is not so much missing bass, but just that its overwhelmed by the highs... Maybe I'll try covering up all the holes and just damping the magnet, see what that does.
 
I also just bought a pair of used 325i drivers from LCfiner here. If I understand correctly, the drivers are attached to a longer (than SR60/80i) plastic sleeve, over which one simply mounts whatever casing, whether it be wood or aluminum. Is this right?
 
I was planning to just stick them in the SR60 cup, but a few threads seem to suggest that its going to sound more like a 125i than a 325i if I do that. Does anybody here have specs for the 325i's enclosure?

 
When you get to the first aid section, ensure you get the micropore tape, not the transpore tape.  On the back of the package, it will provide the "medical" name for the tape in small letters.
 
Yes, adding a bit of mass to dampen the rear of the driver is the objective.  In the past, we thought it had something to do with the bass mods, but it appears the opposite might be truer.
 
I'm not sure of the specific depth of the 325 driver sleeves.  However, if you're considering wooden cups, you should consider "liberating" the driver from the plastic sleeve itself.  If you mount the driver, with the sleeve into a wooden cup, you'll never be able to take full advantage of all that the wood offers.  In the SR-60 mod thread, I documented a process for liberating the driver with pictures.  I used a few small blocks of wood, a wire side-cutter and a "C" clamp to accomplish the process.  In the end, the driver was neatly pressed out of the sleeve.  Others have just hacked at the sleeve - completely destroying it to get the driver liberated.

 

[karthikrr]

Micropore, NOT transpore: Noted!
 
Will look for your instructions on liberating the driver. I didn't know if it was possible to get it out cleanly, but definitely did not want to stick a screwdriver in there and 'hack away'! I assume making a replica of the existing sleeve is ideal?
 
Also, wood or metal, whats the general consensus on that? I am not remotely qualified enough to make these things myself, but I have a friend who owns a wood working factory as well as a metalworks factory, and think I can convince him to churn out some pieces for me. I just need to make sure I give him the right specs.
 
I just saw another ancient post where they opined that the cups and depth are not as important as the width of the opening in the back. That seems to be a good explanation as to why the SR60 sounded so much better without the back cap, since the opening is the width of the driver. I'm sure many have tried and reported this already, but its going to take me a few months to pore through 500 plus pages of mods Any thoughts on making a cap that was wider, so that the grill had the same dia as the driver?
 
Thanks again for the tips!