SR60-Mod
Jan 15, 2011 at 2:46 PM Post #796 of 5,004


Quote:
After seeing Bills video's I'm going for the Coccobolo, what the hell you only live once. I think some kind of screen or mesh that is Brass or that bright gold color would look sharp with the Coccobolo, and I have zero idea if I'm even close to spelling Coccobolo correctly...
 
intox- I think you cover the holes with Dynamat to correct??
 


I have a brass screen, and I don't think it looks good with cocobolo. YMMV
 
Jan 15, 2011 at 2:58 PM Post #798 of 5,004
Brass screens,like parachutes,are for sissy's
tongue.gif

 
Jan 15, 2011 at 3:10 PM Post #800 of 5,004

 
Quote:
OK guys... My 125i cans are now modified...
 
1) opened with hair dryer
2) cleaned off all remaining glue
3) punched 4 holes on each can
4) added 3/4 inch diameter felt furniture pad on metal center of each driver
5) added a strip of electrical tape around smaller half to hold the two halves together. Just makes them tights so I can easily reopen them... no glue yet.
6) using a pair pf Grado L-Cusions
 
The base is greater. Maybe a tad too boomy...a little more open with better soundstage... still evaluating.
 
Next step is some more work of the inside and replacement of the outside plastic screen and button. Questions...
 
1) Are we dampening the chamber or trying to absorb hi frequency reflections? Is seems that something like Dynamat would do the former. I have some that I had bought to dampen a turntable. It is a 12" square with removable paper on one side that exposes the sticky side. The other side has a heavy foil. Is that what some of you have used? If so, that would leave the foil facing the inside of the can. Now I've seen some of you line the inside with stick-on felt strips. It seems that would not dampen, but more likely absorb high frequencies. I'm not a sound engineer... just thinking out loud.
 
2) How do you remove the existing plastic screen on the outside of the cans? It is glued on the inside of the larger half.  (the mesh that contains the button with the model number)


OK... the further adventures... This morning's work on the SR125i cans
 
1) opened them up again. (easy right now, no glue. I just have some electrical tape around the outside of the driver half for a friction fit of the two halves) 
2) removed the (previously installed)  felt furniture foot pad from the back of the driver's center.
3) replaced that felt pad with a round 3/4 inch diameter piece of Dynamat.
4) cut 3/8 inch wide strips of Dynamat and put those around the inside of both halves of the cans. 
5) when assembled now the entire inside walls are covered with Dynamat.
6) removed the plastic outer screen and "model number" button.
7) cleaned up the inside where that screen was glued, using Dremel and sand paper.
8) replaced the screen with pieces of a wire mesh cut from a Hershey's Kiss can. Not sure of the material but it's a shiny metal.
9) actually the screen was replaced before sticking the Daynamat to the inside of the outer cups. The Dynamat is all that is holding the new screens in for now.
10) from all of my work to date, the paint was coming off the lettering on the outside of the cup.
11) so I simply buffed off the remaining paint with 400 grit sand paper and cleaned it up. the lettering is now simply black.
12) Still using the Grado L-Cusion ear pads.
 
All of the Dynamat seems to have tightened up the low end a little. I will stop all mods for now and spend several days evaluating what I have done. It's a shame that I do not have a stock pair of SR125i cans for comparison. There is still a chance that I will go back in and cover 2 of the 4 holes that I opened.
 
 
 
Jan 15, 2011 at 3:27 PM Post #801 of 5,004


Quote:
What does dynamat do exactly ? Reduce noise ? Reduce vibrations ?
Because I'm in France and dynamat is not available here.

 
Dynamat is simply a soft gooey rubber that comes in sheets. It's primary use is to reduce (dampen)  vibrations. Mine has a heavy aluminum foil on one side (this remains) and a peel-off paper on the other. So you just peel and stick. It is used a great deal in the installation of car stereo systems. You stick it on thin metal areas around speakers to stop vibrations. I had some that I had used to dampen metal and wooden areas on the inside of my turntable. I guess the theory behind using vcin the plastic Grado cans is to dampen any vibrations that may be taking place on the back side of the speaker drivers.
 
I've read some material by stereo speaker designers about what takes place on the back side of speakers. They go to great lengths to absorb, or deflect, or channel away all sound waves from the back of their speakers. They do not want any reflections bouncing and returning to the back side of the drivers, causing distortion.
 
So I'm not really sure what we want/need (if anything) on the inside of these cans. 1) something to absorb the sound waves from the back of the drivers... 2) something to dampen and resonance behind the drivers... or 3) something to just direct the sound waves away from the back of the drivers... or 4) some combination of these three.
 
Jan 15, 2011 at 3:39 PM Post #802 of 5,004
What does dynamat do exactly ? Reduce noise ? Reduce vibrations ?
Because I'm in France and dynamat is not available here.


Dynamat is a thin, gummy material with an aluminum-foil type of backing.  It's used in the car-stereo industry.  The boomy bass in car stereos can produce so much vibration that the vehicle, itself, starts acting like a speaker, but in the worst possible way.  Without proper sound damping, you get a lot of rattling, along with a buzz.  Some may argue that there isn't enough sound pumping through the Grados, let alone bass, to merit the Dynamat.  I was slow to give it a try.  It's expensive.  It seems like there are cheaper alternatives.  But after finally trying it, I can't say enough on its behalf.  I made Dynamat the last of a series of mods I recently made to a pair of SR60s, including the use of cocobolo.  I got my cans about as good as I could get them, minus a cable upgrade and leather for the pads and headband.  By this point, any improvements to performance should have been relatively minor.  Nevertheless, the moment I stuck the Dynamat on, I clearly heard another jump in performance.  Detail retrieval was really, really cool.  I lost a lot of sleep the night I tried it because I couldn't get myself to go to bed.
 
Jan 15, 2011 at 4:25 PM Post #803 of 5,004
Ah...poor thing...too bad for you. it worked famously for me. Eliminated a buzzing issue I was having after doing the vent mod to my SR325's.
 
BTW...I have a small supply of Dynamat if anyone wants to try it. PM me and I'll get some out to you no charge. I have enough to do maybe 12-15 pairs.
 
Quote:
Quote:
What does dynamat do exactly ? Reduce noise ? Reduce vibrations ?
Because I'm in France and dynamat is not available here.


I hate to say it ,but dynamat is for sissy's as well.I have tried it twice,never worked for me....

 
Jan 15, 2011 at 4:45 PM Post #804 of 5,004
Ah...poor thing...too bad for you. it worked famously for me. Eliminated a buzzing issue I was having after doing the vent mod to my SR325's.
 
BTW...I have a small supply of Dynamat if anyone wants to try it. PM me and I'll get some out to you no charge. I have enough to do maybe 12-15 pairs.
 
Quote:
Quote:
What does dynamat do exactly ? Reduce noise ? Reduce vibrations ?
Because I'm in France and dynamat is not available here.


I hate to say it ,but dynamat is for sissy's as well.I have tried it twice,never worked for me....


I'm planning on getting some, what kind do you use? They have different thicknesses, and different kinds, and I'm guessing it affects the cans differently, so what kind do you guys use?
 
Jan 15, 2011 at 5:17 PM Post #805 of 5,004
I have Dynamat Xtreme...their top of the line stuff. There are other brands used in car audio that are as good or better than Dynamat but it is costly, especially if you just want two dime sized pieces for your headphones...lol
 
Jan 15, 2011 at 5:51 PM Post #806 of 5,004
I have Dynamat Xtreme...their top of the line stuff. There are other brands used in car audio that are as good or better than Dynamat but it is costly, especially if you just want two dime sized pieces for your headphones...lol


Yeah, I was looking at Xtreme. In store, I only have a $60 subwoofer kit available. Guess I need to order the 10"x10" since I'll barely use any. At least it's under $20.
 
Jan 15, 2011 at 6:08 PM Post #807 of 5,004
If you are only doing one or two pairs...send me your address and I'll send you enough to do them for free.
 
Jan 15, 2011 at 6:23 PM Post #809 of 5,004
No love for the brass screen?? What looks best with Coccobollo Black??? Silver? Orange-I'm thinking Orange, I like Orange....LOL.
I got my Musical Paradise MP-301 today and its rocking some Grado's, JBL's, fun stuff...
 
Jan 15, 2011 at 6:46 PM Post #810 of 5,004
Well that went less than optimally.
 
Got the cups apart after a ton of effort (using a spoon and hairdryer) and got 4 holes poked in the fabric of each driver. However I couldn't leave well enough alone and tried to take my buttons off. After heating each for about 2 minutes with a hairdryer I tried neednose pliers. My result is that I now have two nice jagged holes in the middle of each screen.
 
I guess I will be hitting Walmart again tomorrow for some screen patches and letter trays to make new grills. I will also be investigating what size hole saws I have (have a bunch as far as I know). I have a friend with a drill press I will be visiting. I am hoping I can get a reasonably sized piece of mahoganey at Home Depot or Lowes so I can play around with cups.
 

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