Damping Mechanical Energy Distortion of STAX and other phones with SORBOTHANE and other materials.

[nick n]

Thanks for all the info in here especially the updates, application methods ( strips vs sections ) and thickness preferences.
 
Got some mods on the go sometime soonish I hope will check out the 30D adhesive backed 1/10" stuff.
Better than Dynamat Extreme I would assume

 

[nabwong]

I've never been one to mod my headphones. I appreciate that different makers have different ideas of good sound and they probably have a lot more knowledge than I do in engineering and acoustic terms. That said, maybe damping has been an oversight? 

My experience with damping the HE-400 has opened my eyes. The difference is not subtle, it's jaw dropping. Don't get me wrong, it has not changed the sound signature or character of the HE-400. It is still quick, energetic and fun. What the damping did was to make it clean. It's almost like surgical cleansing; you just killed all the germs. In this case, unwanted noise is eliminated. Look, i'm not an engineer. So I can't quantify it for you and I have no desire to. I'm a musician and when I listen to a damped HE-400, i'm marveled by how clean and well defined the sound is now. 

Speaking of well defined sound, much of that I feel is due to the increased rate of decay. There is just the right amount of space now between sounds. It was just slightly bleeding over before, in the highs especially. I think that did a lot to cover up the mids. Now that the dust has been wiped off the window, I can see clearly. 

The other thing that is apparent is how much heftier the sound is, not that it was anorexic before but it just has a little more weight to the sound. To me, it's like the difference between bouncing a volleyball and a basketball. One's a little denser, weightier and bounces better. The bounce sounds better too. I think the weight is more proportioned to the speed of the attack. Ping pong balls are now golf balls. Overall, it just gives a feeling of solidness. It doesn't light up or distort when you push it. As susceptible to interference. Another way to explain it is like having a bad or good tripod. The good tripod doesn't transfer the vibration to the camera, so you can take longer exposure pictures without worrying that the picture will get too noisy.

Can you overdo the damping? I'm sure. I think we all have to find the right balance for ourselves. I've been listening to all sorts of music and I've been impressed every single time. Lorde, Herbie Hancock, Mahler, Acoustic stuff, Dave Brubeck, Piazzolla, Green Day. I'm in love with the HE-400. I think the driver is competent enough. All it needed was a little fine tuning. 

*lined the inside of the he-400 and then closed the grill. Used 1/10" thick, 50 duro 3m adhesive.



*also did the inside of my yamaha mt220. Significantly "cleaner" but also heftier sound.

 

[MrMateoHead]

   I have seen that there are some professional modders out there who apply dynamat to headphones (and charge exorbitant amounts for this)   As far as I understand, dynamat is designed to block external sound, such as road noise, getting into cars.  To the extent that it also dampens vibrations it is doing the same thing as sorbothane. I, or someone else  ought to try it with headphones and compare it to sorb. There really is a lot of research that needs to be done here.

Dynamat also "deadens" cars by adding weight/mass to door and floor panels. I assume that to some extent doing this to the plastic cups is killing external noise / internal resonances / vibrations. There seems to be quite a lot of good performance data at their website - maybe a more technical person can tell us more about what is there.

 

[Eurobeat]

IMO you might want something like this.

http://www.amazon.com/Isolate-It-Sorbothane-Acoustic-Vibration/dp/B00A4E0CL4/ref=pd_sim_sbs_328_3?ie=UTF8&refRID=1RZ4CFKQRJABF0C5ZC28&dpSrc=sims&dpST=_AC_UL160_SR160%2C160_

"Accoustic and Sound Dampening?"

I was looking at this last night when I was really tired, but now that I think about it, I hope it wouldn't cut the sound...

It soundedl ike something we would want... though?

 

[edstrelow]

  IMO you might want something like this.

http://www.amazon.com/Isolate-It-Sorbothane-Acoustic-Vibration/dp/B00A4E0CL4/ref=pd_sim_sbs_328_3?ie=UTF8&refRID=1RZ4CFKQRJABF0C5ZC28&dpSrc=sims&dpST=_AC_UL160_SR160%2C160_

"Accoustic and Sound Dampening?"

I was looking at this last night when I was really tired, but now that I think about it, I hope it wouldn't cut the sound...

It soundedl ike something we would want... though?

Looks like the type of sorb I and others have been trying.  Two points , though: this is a pretty large sheet and is a lot more than you would need for one phone.  As well, it is 50 duro, which means it is stiffer than the 30 duro I have been generally using. However my use of 30 duro is only based on a hunch that softer sorb is better than harder.   I haven't made a direct comparison between harder and stiffer sorb. There is a lot we don't know on this topic.
 

 
Dynamat also "deadens" cars by adding weight/mass to door and floor panels. I assume that to some extent doing this to the plastic cups is killing external noise / internal resonances / vibrations. There seems to be quite a lot of good performance data at their website - maybe a more technical person can tell us more about what is there.

I suspect that dynamat will have at least some of the properties of sorbothane although it seems to be primarily designed to block sound rather than absorb it and convert it to heat as is claimed for sorbothane.  As I say above, there is a lot we just don't know about how to proceed here and a lot of experimentation needed.
 

I've never been one to mod my headphones. I appreciate that different makers have different ideas of good sound and they probably have a lot more knowledge than I do in engineering and acoustic terms. That said, maybe damping has been an oversight? 

My experience with damping the HE-400 has opened my eyes. The difference is not subtle, it's jaw dropping. Don't get me wrong, it has not changed the sound signature or character of the HE-400. It is still quick, energetic and fun. What the damping did was to make it clean. It's almost like surgical cleansing; you just killed all the germs. In this case, unwanted noise is eliminated. Look, i'm not an engineer. So I can't quantify it for you and I have no desire to. I'm a musician and when I listen to a damped HE-400, i'm marveled by how clean and well defined the sound is now. 

Speaking of well defined sound, much of that I feel is due to the increased rate of decay. There is just the right amount of space now between sounds. It was just slightly bleeding over before, in the highs especially. I think that did a lot to cover up the mids. Now that the dust has been wiped off the window, I can see clearly. 

The other thing that is apparent is how much heftier the sound is, not that it was anorexic before but it just has a little more weight to the sound. To me, it's like the difference between bouncing a volleyball and a basketball. One's a little denser, weightier and bounces better. The bounce sounds better too. I think the weight is more proportioned to the speed of the attack. Ping pong balls are now golf balls. Overall, it just gives a feeling of solidness. It doesn't light up or distort when you push it. As susceptible to interference. Another way to explain it is like having a bad or good tripod. The good tripod doesn't transfer the vibration to the camera, so you can take longer exposure pictures without worrying that the picture will get too noisy.

Can you overdo the damping? I'm sure. I think we all have to find the right balance for ourselves. I've been listening to all sorts of music and I've been impressed every single time. Lorde, Herbie Hancock, Mahler, Acoustic stuff, Dave Brubeck, Piazzolla, Green Day. I'm in love with the HE-400. I think the driver is competent enough. All it needed was a little fine tuning. 

*lined the inside of the he-400 and then closed the grill. Used 1/10" thick, 50 duro 3m adhesive.



*also did the inside of my yamaha mt220. Significantly "cleaner" but also heftier sound.

Sounds like you have found a sweet spot for damping these phones.

 

[nabwong]

 
Sounds like you have found a sweet spot for damping these phones.

 
I'm wondering how the hardness affects the sound but for right now, it's sounding pretty awesome. 

 

[Eurobeat]

  Looks like the type of sorb I and others have been trying.  Two points , though: this is a pretty large sheet and is a lot more than you would need for one phone.  As well, it is 50 duro, which means it is stiffer than the 30 duro I have been generally using. However my use of 30 duro is only based on a hunch that softer sorb is better than harder.   I haven't made a direct comparison between harder and stiffer sorb. There is a lot we don't know on this topic.

It seems there are 2 kinds. "Accoustic and Vibration dampening" and "vibration dampening."  I wonder if the acoustic would hurt the music, or work better?  I would assuming "acoustic dampening" would refer to making a silent room, or something...  

Not sure if we should test the difference, or not..  Maybe I'll contact the company and get the info .

I'm not sure which ones to get (duros), but I thought someone mentioned 50.

I think I'll give the company a chat, and see what they believe is the best options for our headphones, and then I will post here with some info .

 

[richard51]

very good idea... thanks i will wait  for

their answer...

 

[MrMateoHead]

Well my research into the subject is that Dynamat is also a visco-elastic material (Buytl Rubber), which is different than Sorbathane but Sorbathane has comparison data showing that it is a superior damping agent (shock, vibration, impact) compared to Buytl rubber. In short, dynamat has always been a "room treatment" which leads to better sound - primarily by lowering the noise floor of cars.
 
Considering that the typical vehicle will have peak noise near 80 dB under accelaration and highway noise of 70 dB +- 4 dB, and that dynamat can reduce this by 3-18 dB, this is extremely significant. As you know, cutting road noise by just 3-6 dB would allow you to reduce your power roughly by half to achieve the same volume. When I am cruising the highway, I need my deck at minimum volume 17-20 to significantly overcome road noise, and my setup clips around 23-25 on the dial (out of 35 - I know - the preouts suck on that deck or the DSP does whatever). In any case, I am listening at significantly over 70 dB at that point - probably 75 dB + peaks - not great for my hearing long-term and harder on the equipment. I won't dynamat my car (don't feel like it) but I can imagine the stuff could do wonders in terms of improving the listening experience + reduce driver and ear fatigue. Assuming I got a reduction of road noise of 10 dB or so, I would likely achieve comfortable listening at lower volumes, and could do things like EQ aggressively without worrying about clipping.
 
SO when we are using sorbathane on these headphones we are seeking better sound by treating the speaker's "room" - in this case round plastic ear cups with mesh on the ear end promoting sound transfer, and wire mesh + fabric on the other end which allows transfer but must, as a result of the grill, result in some reflection of the back wave (hence the grill mods that "improve" the sound). I think the basic assumption is that the HE-400s are living in a very "live" room, where reflections and energy are not dissipating enough prior to reaching our ears. But it is the back wave firing "through the room", while our ears are in either a "pleather room", or a "velour room", the former probably closed cell foam, the latter might be open (slightly more absorptive but modded pleathers certainly are better damped).
 
I would think the only reason to use higher duro values would be to gain tear resistance, or use with heavier objects as the softer duro probably deforms a bit more easily. I want to try 30 duro patches, and probably apply some to the back of the driver frame, to really prevent the backwave from traveling back through the cup, and possible to quell slight vibrations that may be in the driver housing? But obviously, overdamping the headphones could sound worse. Then there is choosing thickness - how much space is there between the grill and the driver housing? Could .25 inch fit better than 1/10 inch?

 

[nabwong]

  Well my research into the subject is that Dynamat is also a visco-elastic material (Buytl Rubber), which is different than Sorbathane but Sorbathane has comparison data showing that it is a superior damping agent (shock, vibration, impact) compared to Buytl rubber. In short, dynamat has always been a "room treatment" which leads to better sound - primarily by lowering the noise floor of cars.
 
Considering that the typical vehicle will have peak noise near 80 dB under accelaration and highway noise of 70 dB +- 4 dB, and that dynamat can reduce this by 3-18 dB, this is extremely significant. As you know, cutting road noise by just 3-6 dB would allow you to reduce your power roughly by half to achieve the same volume. When I am cruising the highway, I need my deck at minimum volume 17-20 to significantly overcome road noise, and my setup clips around 23-25 on the dial (out of 35 - I know - the preouts suck on that deck or the DSP does whatever). In any case, I am listening at significantly over 70 dB at that point - probably 75 dB + peaks - not great for my hearing long-term and harder on the equipment. I won't dynamat my car (don't feel like it) but I can imagine the stuff could do wonders in terms of improving the listening experience + reduce driver and ear fatigue. Assuming I got a reduction of road noise of 10 dB or so, I would likely achieve comfortable listening at lower volumes, and could do things like EQ aggressively without worrying about clipping.
 
SO when we are using sorbathane on these headphones we are seeking better sound by treating the speaker's "room" - in this case round plastic ear cups with mesh on the ear end promoting sound transfer, and wire mesh + fabric on the other end which allows transfer but must, as a result of the grill, result in some reflection of the back wave (hence the grill mods that "improve" the sound). I think the basic assumption is that the HE-400s are living in a very "live" room, where reflections and energy are not dissipating enough prior to reaching our ears. But it is the back wave firing "through the room", while our ears are in either a "pleather room", or a "velour room", the former probably closed cell foam, the latter might be open (slightly more absorptive but modded pleathers certainly are better damped).
 
I would think the only reason to use higher duro values would be to gain tear resistance, or use with heavier objects as the softer duro probably deforms a bit more easily. I want to try 30 duro patches, and probably apply some to the back of the driver frame, to really prevent the backwave from traveling back through the cup, and possible to quell slight vibrations that may be in the driver housing? But obviously, overdamping the headphones could sound worse. Then there is choosing thickness - how much space is there between the grill and the driver housing? Could .25 inch fit better than 1/10 inch?

 
Thanks for adding some useful knowledge to the discussion. I'm really enjoying this thread, compared to the cable and pad threads. Yes, shots fired. lol. 

 

[MrMateoHead]

Just ordered a sheet of 6x6 1/10 30 duro from ebay for $15 bucks. I suppose I can just stick some in my computer case if it doesn't work out lol. I'm going on the theory that the Duro ranking is probably a little less important - but I'd rather have had 1/8 or even 1/4 inch thick stuff if I could find it (40d limit). My guess is that the amount of the stuff + the size of the pads will largely determine the strength of the damping. To those concerned, I doubt it will "reduce the bass". In an untreated room, a flat speaker can sound very "boomy" in the low / mid bass depending on the resonance of the surrounding structures + placement. Its good to "deaden" a room, but you don't want it "dead" - particularly with these, they've tended, if anything, to need a little boost in the 50 hz range.

 

[richard51]

i have 1/8 and 30 duro and the bass was improved...

 

[edstrelow]

  Just ordered a sheet of 6x6 1/10 30 duro from ebay for $15 bucks. I suppose I can just stick some in my computer case if it doesn't work out lol. I'm going on the theory that the Duro ranking is probably a little less important - but I'd rather have had 1/8 or even 1/4 inch thick stuff if I could find it (40d limit). My guess is that the amount of the stuff + the size of the pads will largely determine the strength of the damping. To those concerned, I doubt it will "reduce the bass". In an untreated room, a flat speaker can sound very "boomy" in the low / mid bass depending on the resonance of the surrounding structures + placement. Its good to "deaden" a room, but you don't want it "dead" - particularly with these, they've tended, if anything, to need a little boost in the 50 hz range.

 
 

  i have 1/8 and 30 duro and the bass was improved...

 
I  have not found that bass falls off with damping. In several of my efforts, bass has actually  increased after damping . My explanation is that as a Sorbothane tecnician told me, the dampening ability  of sorbothane  falls off below 50Hz. The sorb generally lowers the volume of those frequencies it damps, presumably because it is abosrbing the resonant energy in those frequencies. If the frequencies less than 50 Hz are not damped, they would end up  proportionately louder,  Of course there is not usually much musical signal there and most phones are somewhat deficient in the bass anyway so this is not usually a problem.
 
However I have noted that loose or poorly installed sorb may give an unpleasant bass boost.  Seems like it may actually vibrate in this situation.
 
When I have used a mechanical clamp to hold the sorbethane, as I still do on the headband of the Stax SR007A, you can to some extent tune the bass.  Tighter clamping seems to reduce bass.
 
Lots of things here that I don't understand.

 

[Eurobeat]

   
 
 
I  have not found that bass falls off with damping. In several of my efforts, bass has actually  increased after damping . My explanation is that as a Sorbothane tecnician told me, the dampening ability  of sorbothane  falls off below 50Hz. The sorb generally lowers the volume of those frequencies it damps, presumably because it is abosrbing the resonant energy in those frequencies. If the frequencies less than 50 Hz are not damped, they would end up  proportionately louder,  Of course there is not usually much musical signal there and most phones are somewhat deficient in the bass anyway so this is not usually a problem.
 
However I have noted that loose or poorly installed sorb may give an unpleasant bass boost.  Seems like it may actually vibrate in this situation.
 
When I have used a mechanical clamp to hold the sorbethane, as I still do on the headband of the Stax SR007A, you can to some extent tune the bass.  Tighter clamping seems to reduce bass.
 
Lots of things here that I don't understand.

So you're saying the frequencies are being altered/lowered?  Wouldn't that affect the entire sound then? Wouldn't it be a lot diffrent/odd?

 

[edstrelow]

You would think the bass would be up, but as I say there is so little music below 50 Hz, if this does happen  it is not obvious. And I should say, I am going on a verbal statement from a technician with no  documentation, such as a graph to back it up.  I  doubt that the the damping factor ends abruptly at 50 Hz, it probably rolls off at that point so it may not be that pronounced. I say try it yourself and see what you hear. That's what matters in the end.