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Dynamat(or similar) and motorcycle helmets.

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I used to use Dynamat sound dampening material in my automobiles and recording studio to attenuate road noise and dampen sound. Has anyone here ever tried adding to inside shell of helmet? Yes, I know helmet weight would increase. I've thought about trying to make the equivalent of a mini sound chamber in the ear area. Experiences?
 
I wouldn't do that. It would interfere with the effectiveness of the eps layer imo. If I wanted a quieter helmet I'd either get earplugs or break off the coin for a quiet helmet.

I rock a schuberth c3 light with a cardo freecom4 currently and it is quiet enough for me. Also, I like the JBL cones. A lot of people say they are tinny and not worth the cash, I like them though.

Just my opinion.
 
I wear earpeace earplugs already. My road helmet is pretty quiet, my ADV helmet not so much.
I hear what you are saying about the eps layer and have heard some similar surmises, but as there are typically voids or contours in the ear area for speaker pockets and such, I think there is room in that area for additional sound dampening material. Maybe I'll try it out on one of the extras. Good discussion! Let's get back to talking cycling!
 
Dynamat is only effective in deadening acoustically live materials like sheet metal or thin glass panes. Even then, it would only work on those materials if they are constructed in ways that are conducive to vibrating without a high degree of attenuation. There are no materials inside the helmet like that. Both the polystyrene foam and the shell are fairly dead acoustically.

I worked part time installing car alarms and audio back in the late 80s and early 90s, when Dynamat first got popular. I've seen it applied in some horrifically ineffective ways, by installers that lack understanding of the engineering methodologies behind acoustic deadening.
 
If it did work in cutting noise another concern would be blocking all the vents.

Currently I just wear earplugs. I've gotten pretty good at putting my helmet and gloves on, getting the Bluetooth synced and music going, then realizing I forgot to put the plugs in so I need to remove the gloves to get the helmet off to get the plugs in my ears.
 
All valid points...I have extra helmets that I can experiment with. Dynamat may not be appropriate, but I'll research other materials. Could be fun project with all that's going on.
 
Pull the visor off I bet a lot of your wind noise is coming from there, the balance from the shield area as they are generally not
designed around higher speed aerodynamics and unless you are eating a lot of someone's roost and need the visor
as you tip your head forward to use it as protection all its really doing is catching air and making noise
 
Being just about deaf in one ear and having a hard time hearing out of the other this topic is of interest to me. When I go to the range I wear an electronic headset that allows me to hear what is being said but deadens the loud shot. Perhaps this technology might could be applied to helmets?
 
If it did work in cutting noise another concern would be blocking all the vents.

Currently I just wear earplugs. ...

Plugs that attenuate 32 decibels with built in speakers. Designed for pilots. Not cheap. Work great for reducing wind and road noise and reproducing communications and music. Another of those things worthy of a little fiscal investment.

I've gotten pretty good at putting my helmet and gloves on, getting the Bluetooth synced and music going, then realizing I forgot to put the plugs in so I need to remove the gloves to get the helmet off to get the plugs in my ears.

So, it isn't just me? Welcome to the aging process.

Being just about deaf in one ear and having a hard time hearing out of the other this topic is of interest to me. When I go to the range I wear an electronic headset that allows me to hear what is being said but deadens the loud shot. Perhaps this technology might could be applied to helmets?

Yes, it can. That's exactly why I bought my plugs in the first place. Bluetooth hooks to my .mp3 player and cell phone. Once set up, all I have to do is turn everything on. I know several people with the same plugs who also Bluetooth their GPSes. Some, all three.
 
Clarity Aloft. It is an older design but works well. The plugs don't really stop sound by physically blocking the pressure waves, it senses the sound waves and broadcasts into your ears the opposites, and the sound waves pretty much cancel each other out. There is an auxiliary plug for input and output and the Bluetooth adapter plugs into that. No batteries, operates plugged in to 12 volt. Requires aircraft plug ins. Not cheap. About $900 for a complete set up for a motorcycle.
 
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That's what it took to crowd out the random rattle of my brains.
 
Due to un-silenced CZ's and shooting way too many large caliber weapons for fun and good old Uncle Sam the phone is always ringing in my left ear. Sure wish we would have known better back in the day.
 
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Some of us did. That's why I can still hear a sleeping baby in the next room breathing.
 
Active noise canceling and large amplitude shut-off are two very different technologies. The ear plugs you wear at the shooting range are rather simple devices that have basically a microphone that listens to the ambient noise and replicate it on earphones that play into the listener's ears. Upon sensing a large amplitude sound (e.g. gun shot) that exceeds a fixed dB threshold, it will momentarily silence the earphones. That's it.

Active noise canceling is a lot trickier. High speed DSP's are used to analyze the noise coming into the earplug and the system attempts to output a waveform of equal amplitude but opposite phase, hopefully summing with the actual noise to produce zero, or near zero, amplitude at the listener's ears. This works best for mechanical noise produced by cyclic devices, such as an engine, as the induced vibrations are generally harmonics (multiples) of the engine RPM. That sort of regular noise is much easier for the DSP to decipher and react to. Also, lower frequency noise are also easier to deal with, mostly because it is generally non-directional and the phase differences are wide enough for the canceling to work well. So things like road noise produced by tire contact with road surface fall into this category.

OTOH, higher and shifting frequency noise (e.g. wind whistling) are more difficult to cancel out.

I know rider friends who have tried noise canceling earphones have reported mixed reviews. Sometimes, they work quite well; other times they produce side effects like a thumping beat, which end up being more annoying than the actual road/wind noise themselves. Some supposedly work better than others, but none are effective 100% of the time.

For myself, I have a set that I bring on commercial flights and they work exceptionally well in that environment. For riding, I still much prefer good old foam earplugs.
 
As mentioned by many here. I always wear ear plugs when I ride. Just as I wear all my gear .....ATGATT.
 
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