Headsets and ear plugs?

[mrkik]

Hi, I am a student pilot with around 7 hours in an R22. Right now I am just borrowing the schools headsets until I can afford my own. Even though the noise is not that significant in these little helicopters, it is still loud. More for my comfort, I have heard of people using ear plugs to help with the noise. ( http://www.faa.gov/pilots/safety/pilotsafetybrochures/media/hearing_brochure.pdf )

 

If I have ear plugs in my ears with the headset over them, how will I be able to hear the radio at all? That is my main question. Has any body tried this before?

 

Thanks, I really appreciate the help. If you have, do you have any advice? Such as what type of ear plugs to get, etc?

[Death2Daleks]

Double hearing protection - always. How I was taught in the Navy to keep my hearing.

 

The ear plugs kill all the surrounding turbine/jet/prop noise. The headset helps double that protection.

 

In order to hear, you just turn up your radios until they're comfortable.

[Hawkeye0001]

I'm flying with earplugs for quite some time now, it really helps. No probs with the radio, as a matter of fact I can understand the radio a lot better without all the other noise. I can certainly tell the difference when leaving them out: I have a serious buzzing sound in my ears after 6hrs of flying.

I know a couple guys that got custom made earplugs molded. Just ask any acoustician to do it for you. They don't come cheap ($100) but they're well worth it.

[gary-mike]

I have never tried the custom molded ones, but I haven't had much discomfort from the soft tapered disposable ones. The old yellow foam cylinder ones and the rubber tripple flange ones bother me after a bit though. Just a thought if you don't want to spend the $100, although if you use them for hours every day the custom may be worth it like Hawkeye said. Another thing I have saw some AF pilots do is using the old yellow foamiesbut not really inserting them in the ear canal, rather they put them in sidewaysin the ear opening. I am guessing the thought was it blocked some of the noise but not quite as much. This was fighter jocks though, and I know from experience the cockpit of a fighter is much quieter than flying in a heli with the doors off, so I don't know if I would try it.

Edited October 24, 2011 by gary-mike

[Wally]

Hi, I am a student pilot with around 7 hours in an R22. Right now I am just borrowing the schools headsets until I can afford my own. Even though the noise is not that significant in these little helicopters, it is still loud. More for my comfort, I have heard of people using ear plugs to help with the noise. ( http://www.faa.gov/p...ng_brochure.pdf )

 

If I have ear plugs in my ears with the headset over them, how will I be able to hear the radio at all? That is my main question. Has any body tried this before?

 

Thanks, I really appreciate the help. If you have, do you have any advice? Such as what type of ear plugs to get, etc?

 

Try it and if you can't hear with the ear plugs in, pull'em out. Easy to do, I fly with ear plugs all the time. My recollection is that before ANR, the ear plug/headset combo was the recommended method. Ear plugs are more effective against high freq and the a muff was more more effective against low freq, you get both in helos.

[r22butters]

If I have ear plugs in my ears with the headset over them, how will I be able to hear the radio at all? That is my main question. Has any body tried this before?

 

The first time I tried wearing plugs with my headset I had trouble hearing the radio, so I cut them in half,...problem solved.

 

I just use the regular ear plugs you find in drugstores (not the orange/yellow tappered ones, they go in too far, and hurt my ears).

[mrkik]

Thank you for the help! I think I will try to figure some things out. $700 noise-cancellation headsets don't fit my budget right now, but $3 ear plugs do!

 

One other question, what sunglasses do you recommend? Obviously this depends on the pilot, but the sunglasses I'm using right now make my headset louder because they ruin the seal over my ear.

[Tarantula]

Non-polarized sunglasses. That's the biggest thing. Polarized ones can cause glass cockpits or GPS/other display screens to be unreadable.

[500F]

Get something that gives you good periphial vision. I like either wraparounds or aviators. I have persciption Maui Jim's that work great

[jimbo2181]

Maui Jims titanium glass are what I could works best. Yes the polarized lens can block lcd screens but most manufactures put the screen on an angle so you can still see it. If not tilt your head 5 degrees and you'll be able to read it fine.

[Rotorhead84]

Try it and if you can't hear with the ear plugs in, pull'em out. Easy to do, I fly with ear plugs all the time. My recollection is that before ANR, the ear plug/headset combo was the recommended method. Ear plugs are more effective against high freq and the a muff was more more effective against low freq, you get both in helos.

 

 

I've always considered earplugs a must!

Edited November 13, 2011 by Rotorhead84

[avbug]

Earplugs under a headset or helmet won't prevent your hearing and understanding the communications. You can always turn them up a bit.

 

Numerous options are available for cockpit communications. Different choices work well for different people. You can put together a good passive headset for not a lot of money. While David Clark has by far the best warranty and customer service when it comes to passive clamp-style headsets, you can turn a lot of those same style headsets into better ones by using the Oregon Aero upgrade kit. It includes a wider sheep wool headband, earseals that mold to your head in response to body heat, and dense foam inserts that go into the earcups to increase their noise attenuating ability. They'll be quieter offer more protection, and you'll be able to hear the communications better.

 

Wearing foam earplugs under the headset is never a bad idea. I prefer the basic yellow EAR plugs.

[aeroscout]

I have a CEP mod. I chose it over ANR because ANR only masks the frequencies, it doesn't prevent hearing loss, at least the way I understand it like a CEP mod will.

[palmfish]

I have a CEP mod. I chose it over ANR because ANR only masks the frequencies, it doesn't prevent hearing loss, at least the way I understand it like a CEP mod will.

 

What do you mean by "masks the frequencies?"

 

Sound is a mechanical wave. A wave either exists or it doesn't. ANR cancels the wave, thus making it no longer exist.

[aeroscout]

What do you mean by "masks the frequencies?"

 

Sound is a mechanical wave. A wave either exists or it doesn't. ANR cancels the wave, thus making it no longer exist.

 

ANR senses a sound wave, and generates an opposite phase sound wave to cancel it, but there is a delay so that both waves are stimulating the eardrum and the cilia, at least the way I understand it. The brain senses the integration as much less noise than the original sound wave, but, the way I understand it, there is less hearing protection provided than by a CEP. If you have some reference to provide, I would be pleased to be better informed.

[palmfish]

ANR senses a sound wave, and generates an opposite phase sound wave to cancel it, but there is a delay so that both waves are stimulating the eardrum and the cilia, at least the way I understand it. The brain senses the integration as much less noise than the original sound wave, but, the way I understand it, there is less hearing protection provided than by a CEP. If you have some reference to provide, I would be pleased to be better informed.

 

If a tree falls in the forest and nobody is there, did it make a sound?

 

There are numerous scientific studies and white papers written by people smarter than me that can explain the effectiveness of ANR. Just search the web...

[Wally]

"ANR senses a sound wave, and generates an opposite phase sound wave to cancel it, but there is a delay so that both waves are stimulating the eardrum and the cilia"? If there's a "delay' in processing and generating, there can't be 2 waves. Once the second, out of phase wave is generated, it cancels the first. One would be exposed for a much reduced period.

[palmfish]

The science behind ANR, though fascinating, is really moot in the discussion of hearing loss.

 

A sound wave is either there, or it isn't. If it's there, it has amplitude that mechanically travels through the inner ear and excites the cilia. The larger the amplitude, the louder the noise. If a sound is perceived as quiet, then it is low in amplitude and it cannot harm your hearing.

 

A loud noise, such as a helicopter, sounds loud if you are standing right next to it. If you stand 50 yards away, it sounds quieter (due primarily to propagation loss through the air). Now walk inside a building and close the door - the helicopter is even quieter now because a wall is absorbing and/or reflecting/scattering the pressure waves. None of these phenomena are "masking" sound. They are attenuating it.

 

ANR samples and cancels pressure waves with 180 degree out of phase noise, thus attenuating it.

 

Each method of noise attenuation has it's advantages and disadvantages. Walls and air attenuate high frequencies better than low frequencies because the wave length is shorter and more easily absorbed/scattered. ANR is more effective vs. low frequencies because the larger wavelength is easier for the DSP to sample and react to. Combine ANR with passive attenuation, and you have the best of both worlds.

 

Regardless of the method used to attenuate noise however, the end result is the same. Less sound = less risk of hearing loss.

[Gomer Pylot]

What you need to look at is the NRR across the complete range of frequencies. Some devices suppress noise much more at some frequencies than others. ANR for example works much better at lower frequencies than at higher ones, because it's much harder to generate the opposite phase waves at very high frequencies, nearing 20,000 cycles per second. Using just ANR, you won't get as much high frequency protection as you need, and those are the frequencies that are most easily damaged. Any device sold for hearing protection in the US must show the NRR across the entire range of normal human hearing, and you should read it before buying. Turbine engines emit lots more high frequency noise than pistons, so you need to be aware of that if you are, or are planning to fly those.

[aeroscout]

Another excellent discussion of a topic.

[palmfish]

More information about "masking."

 

I am music lover and audio enthusiast and coincidently happen to be reading a book by Floyd Toole titled, "Sound Reproduction: The acoustics and psychoacoustics of loudspeakers and rooms."

 

It's primarily a book about how loudspeakers interact with rooms in home theater installations, but Toole does briefly discuss hearing and loudness in the book. In Section 19.1.4 , Toole states, "Masking occurs when the presence of one sound inhibits the perception of another. The most common is that of simultaneous masking, when both sounds coexist." He later describes this with an example of a pure 500Hz tone masking a lower-level 2 kHz tone. The accompanying chart shows that this 500 Hz tone masks a range of frequencies - all lower-level than the masking tone.

 

This discussion leads to an interesting study (and chart) that illustrates masking - that while driving in a car, "music loses much of its bass, timbral subtlety and spacial envelopment. Only in a parking lot or in stop and go traffic can good car audio systems reveal their true excellence."

[Tarantula]

I think ANR is great stuff. Fascinating technology, and effective for what it was designed to do. That said, I do not think ANR is the best thing to use for flying in a helicopter. To quote from this USAARL study

www.usaarl.army.mil/TechReports/98-9.PDF

ANR is a means used to reduce noise levels in a personal hearing protector by measuring the noise in the earcup and reinserting a processed and out-of-phase noise signal back into the earcup through an earphone. The reinserted sound signal combines with the noise originally measured and causes it to be canceled. This out-of-phase canceling technique usually is very effective for low frequencies, below 800 Hertz, but generally is ineffective for higher frequencies. In some designs, the ANR device increases the noise level inside the earcup in the region where ANR crosses zero attenuation.

Also, this website from Lightspeed states:

www.lightspeedaviation.com/content/lightspeedaviation/CustomPages/ANR-101-A-Tutorial-on-Active-Noise-Reduction/Section-3-Airplane-Issues.htm

Remember (from Section 2) that active cancellation works well only in the lower frequencies... it doesn't provide a noticeable dB reduction at frequencies over 500 Hz. Recall also that active systems require some tradeoffs in passive attenuation to support the needed modifications inside the domes. As such, they are not quite as effective in blocking out the higher frequency noise.

 

As a result, I opted for a helmet with CEP. Compared to just a regular headset, it is much quieter. Compared to ANR headsets that I've flown with (Lightspeed Zulu) I would say the CEP is overall quieter. With ANR I hear a high pitched whine in the background, sort of like when someone leaves an old tube TV on. Not many people seem to be able to hear those frequencies but that was a large deciding factor for me to go CEP over ANR. Because I can hear those frequencies, I would like to protect that part of my hearing as much as possible as well, and CEP provides the best overall protection.

 

Lastly, ANR sets take batteries. Even if you fly with spares, how long does it take for you to change them out, and how much hearing damage are you getting while doing so?

[aeroscout]

Another excellent informative thread.

[palmfish]

I think ANR is great stuff. Fascinating technology, and effective for what it was designed to do. That said, I do not think ANR is the best thing to use for flying in a helicopter. To quote from this USAARL study

 

Also, this website from Lightspeed states:

 

 

As a result, I opted for a helmet with CEP. Compared to just a regular headset, it is much quieter. Compared to ANR headsets that I've flown with (Lightspeed Zulu) I would say the CEP is overall quieter. With ANR I hear a high pitched whine in the background, sort of like when someone leaves an old tube TV on. Not many people seem to be able to hear those frequencies but that was a large deciding factor for me to go CEP over ANR. Because I can hear those frequencies, I would like to protect that part of my hearing as much as possible as well, and CEP provides the best overall protection.

 

Lastly, ANR sets take batteries. Even if you fly with spares, how long does it take for you to change them out, and how much hearing damage are you getting while doing so?

 

Interesting articles, I would like to read the full Lightspeed document.

 

FWIW, I use both types - CEP + helmet in helicopters and ANR (Bose A20) in airplanes. Both seem very effective, but as has been discussed many times, they are different. When I wear my helmet, I can definitely hear the low freq sounds getting through. Interestingly, out of curiosity, I once tried wearing foam plugs inside my Bose headset and I didn't like the results. It seemed that low freq sounds that are normally attenuated by the Bose were increased by the foam. My only explanation is that the foam plugs somehow increased bone conduction - at least, that's what it felt like.

 

I'm very interested in this subject and always trying new things. I have significant hearing loss already and am very sensitive to noise as a result. Anything I can find to help save what hearing I have left is worth it's weight in gold.

[Tarantula]

I left the link in my quote but here is a link to the whole series of pages they have on how ANR works. http://www.lightspeedaviation.com/content/lightspeedaviation/CustomPages/ANR-101-A-Tutorial-on-Active-Noise-Reduction.htm

They have another tutorial and a FAQ at http://www.lightspeedaviation.com/content/lightspeedaviation/CustomPages/Headset-Technology.htm

 

Its too bad that in addition to showing typical plane sound levels/frequencies they don't show R22/44 or S300 sound levels/frequencies. I can't seem to find those anywhere on the web.