Sena SMART Helmet --- Coming Soon

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Noise canceling is far from new and is very effective. MC helmets are a good application for it.

 
Not all noise cancellation systems are created equally.

I suspect the one that reportedly did not work well did not cancel noise equally across the frequency spectrum, and may have actually amplified some frequencies. It would be pretty easy to have that happen.

 
Most serious pilots use noise cancelling headsets because they really work and reduce noise-induced fatigue during long flights. I'd love to have it in a helmet but it would have to be removeable so I could put it in a new helmet every 4-5 years. No way I'd pay that much for something I'd have to throw away that soon. I'd pay ~$1000 for something from a reputable company like Bose that could be moved from helmet to helmet.

 
Interesting discussion on noise canceling technology. With a headset, you have pretty much fixed geometry. A helmet, on the other hand, presents variable geometry because everyone doesn't have the same shape head. Helmet speakers will not necessarily be in the same orientation (or distance) from the wearer's ears for everyone. I wonder how much compromise there might be in the factory "tuning" the noise cancelation to the application?

Waiting for reviews!

 
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I'd pay ~$1000 for something from a reputable company like Bose that could be moved from helmet to helmet.
No Offense to you but BOSE is far from a reputable company.....
I'm not an audiophile so I can't speak to their stereos, speakers, etc, but their noise cancelling aviation headsets are the industry standard.

 
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Interesting discussion on noise canceling technology. With a headset, you have pretty much fixed geometry. A helmet, on the other hand, presents variable geometry because everyone doesn't have the same shape head. Helmet speakers will not necessarily be in the same orientation (or distance) from the wearer's ears for everyone. I wonder how much compromise there might be in the factory "tuning" the noise cancelation to the application?
My understanding of how active noise cancellation works is that the system has a "noise sensor" (basically microphone) to sample the noise, and has a transducer / emitter that broadcasts sound waves at the same frequency but 180 phase reversed from the offending noise. The two sound pressure waves subtract from each other, ideally to the point of total cancellation.

Assuming I have it right, it would be critical for the dimensions between the sensor and the transducer to be fixed and known, in relationship to each other in a helmet. The distance between the transducer (speaker) and the eardrum would be of no particular significance if the sound pressure waves are already nullified outside your ear canal.

Maximum attenuation would happen when the phase difference of the noise and cancellation signal is zero degrees, but for the sake of this discussion let's say that an error within about 30 degrees tolerance (+/-15 degrees) or about ~ 1/10th of the acoustic wavelength would result in reasonably good cancellation. The wavelength of the highest audible frequency (20Khz) is 1.716 cm in 20 degree air, so the sensor to transducer distance would need to be fixed to within less than 2 mm (+/- 1mm) of each other. Longer wavelengths (lower frequencies) would be easier to cancel.

And then there is the whole amplitude thing...

 
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Riddle me this: how is noise canceling beneficial in the long run? I mean, sure , right now, it seems quieter while riding. But doesn't a noise canceling system generate a noise to cancel out the noise? Isn't that twice the work for the ear innards? How is it not damaging your hearing?
I ask b/c I tried noise canceling earbuds one time. Yeah, in the short term they worked great. But after a few hrs I got splitting headaches. Stopped using them--> no more headaches.
Interesting. I, along with many other helicopter pilots have been using noise cancelling headsets since the early 90's. They we're without a doubt the best equipment expenditure, I've ever made as the ANR system reduced fatigue greatly over many hours behind the stick. I'm not saying you didn't have a bad experience, but perhaps the system you tried wasn't functioning properly or was not designed for the conditions you encountered. Active Noise Reduction is awesome technology and it's about time motorcycle helmet manufacturers stepped up to the plate. Hopefully reviews are favorable indicating Sena got it right the first time around.
We use Telex Airman 850s in the jets. I can't imagine how fatiguing it'd be after 12 hours without ANR.

 
My understanding of how active noise cancellation works is that the system has a "noise sensor" (basically microphone) to sample the noise, and has a transducer / emitter that broadcasts sound waves at the same frequency but 180 phase reversed from the offending noise. The two sound pressure waves subtract from each other, ideally to the point of total cancellation.
Correct, but...

Your incoming sound waves are, for all intents and purposes, parallel waves emanating from a point some distance away while the counter wave is essentially a point source within the helmet. When peak meets trough, you have canceling but when peak meets peak, you will have amplification - same as two tower AM radio broadcast. Since the noise point-of-origin cannot be in the same place as the sensor and counter emitter, the effectiveness of noise cancellation will be a function of the algorithms used to tune the environment and the placement of the receiver(ear) within the environment. These are easier to control with a headset in fixed position over the ear than with speakers that are a greater (and variable) distance from the ear. The closer that the internal microphone is in relation to the ear, the better a system like this can work.

 
Sena has been pretty darn good about constant evolution and refinement of their BT comm systems (unlike Garmin!). But Sena was also quick to bring their BT product to market and then produce rapid and frequent firmware releases to work through the real-life variables. One of my questions is how much field testing they will do, how long they will wait, before releasing the production product?

There are some very serious liability concerns if they screw up the ANR enough to damage someone's hearing, even if the user was just plain stupid.

It's all too late for me, my world rings constantly. But I wouldn't mind investing some serious $$$ to help keep what little hearing I do have. Seems like a worthwhile application of well-established technology.

Battery life and battery replacement are primary concerns for me as this point. I only stop to pee and I'm not charging my damn helmet during lunch.

 
My understanding of how active noise cancellation works is that the system has a "noise sensor" (basically microphone) to sample the noise, and has a transducer / emitter that broadcasts sound waves at the same frequency but 180 phase reversed from the offending noise. The two sound pressure waves subtract from each other, ideally to the point of total cancellation.
Correct, but...

Your incoming sound waves are, for all intents and purposes, parallel waves emanating from a point some distance away while the counter wave is essentially a point source within the helmet. When peak meets trough, you have canceling but when peak meets peak, you will have amplification - same as two tower AM radio broadcast. Since the noise point-of-origin cannot be in the same place as the sensor and counter emitter, the effectiveness of noise cancellation will be a function of the algorithms used to tune the environment and the placement of the receiver(ear) within the environment.
No, I do not think the distance to the noise source is of any significance at all. The sensor will detect the amplitude and frequency of the passing pressure waves, and knowing the fixed distance to the transducer (speaker) can generate opposite phased pressure waves of the same amplitude, regardless of from where they originated. Once canceled, the distance from the speaker to the user's eardrum is likewise insignificant.

I've had some first hand experience with EMF cancellation systems (active magnetic shielding) and they work on a similar principle, but with electromagnetic noise (flux waves) rather than sound waves. The trickiest part is dialing in the gain and phase delays for the amplifiers between the stationary sensor and the transducer.

edit: On further reading of your reply,you may be on to something. If what you were saying was that the noise waves from far away would be essentially straight and parallel, but the waves from the speaker closer to your ear would be more curved, and so the curved cancellation wave would not be spatially effective at all angles from the transducer, then you may be right. They would have to make a shaped transducer that simulates flat (less curved) sound waves or the device would only be effective in the one general direction (a line from the sensor through the speaker).

 
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That's what I was getting at. If the pickup microphone is close to the ear and the sound transducer is in a similar position, the difference in the shape of the sound waves could be less important. I wonder if there are separate pickups and emitters for each ear?

 
I cant wait to test one. I'm going to see if I can get one to demo from my supplier early.

I have always worn ear plugs on longer rides/trips and riding without them while killing wind noise is a good thing. I do wonder how fitment will be as others have mentioned. The ear pockets seem generous but one would think they will still need to move around 1/2 in any direction.

The quality of sound that this should be able to reproduce will be very interesting indeed.

Group buy anyone?
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I can't see it happening any time soon. Remember the Skully? $500 down, $950 when it ships. And here we are more than a year and a half later and nothing. Nada. Zip. Maybe I'm just jaded but it seems to me to be the 3.0 upgrade to the Nigerian scam.

 
I agree with BigOrge, why develop their own helmet?? Spend the R&D money used to develop the helmet on making the product better. While that is happening work a deal with Aria and Bell, who are light years ahead of where they'd be in helmet technology, and keep moving.

I'm pretty surprised Aria and Bell haven't teamed up with someone and nailed down that piece of the market.

 
deang posted: I agree with BigOrge, why develop their own helmet?? Spend the R&D money used to develop the helmet on making the product better. While that is happening work a deal with Aria and Bell, who are light years ahead of where they'd be in helmet technology, and keep moving.
I'm pretty surprised Aria and Bell haven't teamed up with someone and nailed down that piece of the market.
a. See my earlier post. My guess is that Sena has a contract with a helmet manufacturer for X number of hats built to their dimensions. Let the helmet manufacturer worry about build details and DOT testing.

b. I also am disappointed that my favorite helmet brand hasn't built something to internalize a Sena device. Would make operations easier, reduce wind noise, yadda, yadda, yadda. I suppose the Sena boys and girls are asking for a significant "licensing fee" or some such, but there are also details to work out like mounting, wire routing, battery position and recharge, etc.

c. Would be nice for a built-in device to use a large FM antenna cast into the helmet frame. Doesn't Nolan or Schuberth do something like that?

 
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My main concern is the safety factor, no mention of certifications. If it is only DOT I am not interested. Needs to have ECE 22-05 or Snell M2015 for me to be seriously interested. Noggin safety first, gizmo's second.

 
Rumor is that the helmet is made by the folks who make Nexx helmets. If true, this is not for me (I own a Nexx and the build quality is sh*t). In fact, it's not for me anyway. I'll stick with my Schuberth C3.

 
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