Are there any true effective ways to reduce the noise of a Mooney?

[midlifeflyer]

52 minutes ago, LANCECASPER said:

Whichever of the in-ear models allow you to use molds to get earplugs for your own ears (perhaps made through an audiologist's office) might be the best way to reduce noise where it counts - the noise which is allowed to enter into your ears.

Blocking noise before entering the ear canal is the whole idea behind in-ear headsets. Although some add ANR capability (and need it!!), the basics of Clarity, Halo, Axis and several others is the use of acoustical foam that goes deeper into the ear canal than music IEMs to seal the ear canal - like foam earplugs used on noisy work sites.  

I'm pretty sure you can get custom ear plugs for all of them. I've heard that you can even get them for the knock-off IFQ headset which has kind of weird-shaped earpieces. 

Interestingly, Clarity recommends against custom plugs (yes, they are available).  According to Clarity, the Comply foam eartips  will produce a better seal, are less inclined to lose the seal with head turning, etc, and are 5 dB quieter overall. 

I have a friend who uses custom ear molds. I've been thinking of having them try mine and compare (I have a bunch of extra eartips so I can do demos for friends who are interested in mine).

[Will.iam]

Insteresting I have not heard of AXIS headset either, novel idea of having the band go at a 45 angle around the head, also the connection where the tubes go to the band seem to be where you would want to put your sunglasses at. I have wanted to try the CQ1 headset from CMW only for the fact the owners had tried Clarity Alofts and Halo headsets and were not impressed with certain things with each so they designed their own which the acrobatic communities love because the boom mic stays in place and are superlight weight. also with the mic gain being adjustable can be used in different noise environment airplanes like jets.  Wonder if there is a review comparing the AXIS with the CQ1 somewhere. 

[A64Pilot]

Years ago when flying Military helicopters we had no ANR but our helmets were very good at passive reduction, a helicopter is much louder than an airplane.

Anyway when I was in Savannah decades ago I had a set of custom ear molds I guess you would call them made, they can be made to block different frequencies. there is a passage in them that allows sound through and they shape that passage to block certain frequencies or in the case for musicians they block all frequencies evenly. Mine blocked high frequencies what the threshold is I don’t know. I don’t think they are special pilot ones, probably the one for people that work in loud factories etc.

After the Military I flew Crop Dusters for I think 17 years, and as they have zero insulation or even any fabric interior they are louder than our Mooney’s. Cockpit is a thin metal box. I did have ANR in my helmets though and still wore the custom ear plugs made by the Audiologist.

Here’s the thing about ANR, it only works between 50 and 300 Hz frequencies that are annoying and any noise causes fatigue, but the frequencies that ANR blocks isn’t really very damaging, high frequencies cause the greatest hearing loss. So headsets that are poor passive headsets and rely heavily on ANR aren’t very good at protecting from hearing loss, you need to block the high frequencies.

Long story short in 40 years and over 10,000 hours flying I have very little hearing loss, I believe about what the average office worker my age does, but I’ve worn hearing protection for decades anytime I mow the grass or whatever.

I do have Tinnitus though, I think it’s likely age related? 

Oh, and at one of our classes long ago we had the Dr tell us an easy way to determine if your accumulating hearing damage.

It was when you get in your car in the morning to come to work if the radio seems loud, then it’s likely your accumulating hearing damage, if you don’t turn the radio down then your probably not.

[midlifeflyer]

2 hours ago, Will.iam said:

Insteresting I have not heard of AXIS headset either, novel idea of having the band go at a 45 angle around the head, also the connection where the tubes go to the band seem to be where you would want to put your sunglasses at. I have wanted to try the CQ1 headset from CMW only for the fact the owners had tried Clarity Alofts and Halo headsets and were not impressed with certain things with each so they designed their own which the acrobatic communities love because the boom mic stays in place and are superlight weight. also with the mic gain being adjustable can be used in different noise environment airplanes like jets.  Wonder if there is a review comparing the AXIS with the CQ1 somewhere. 

I haven't seen one. Almost ordered it but was extremely happy with the Axis.

I would expect both to have similar noise attenuation properties. They both use the same 3M tips as the Halo (they are used by audiologists for hearing tests and can be purchased in volume cheaply) as well as the Comply foam. (There are, btw, a few other options.) The mic boom not staying in place is the reason I didn't keep the Halo when I tried them. It definitely stays in place on the Axis. 

If you are in the market, both have a 30 day return policy.

[Bolter]

On 9/7/2024 at 6:54 AM, Schllc said:

There is a free sound app called decibel x you can download for the phone. 
see if the reduction is significant as you perceive. 

In addition to the dB level, use an app like these to see the frequency content of the sound.  It may help pinpoint what is the causing the issue.  For example, if you have a 2 bladed prop make noise at 2x engine rpm and that is the irritant, then 3 and 4 blade props would increase the frequency from your sensitive range, making the amplitude irrelevant.  Possibly.  If it is the pure engine RPM, you may not be able to do anything, except maybe an exhaust tip to redirect sound.  If it was wind noise, sealing around the door will make a difference.  

From my very little research, the sensitivity to frequency of the typical human is not matching the dBa curve very well.  If you went to audiologist, you may know exactly which frequencies bother you most.  

Android app: https://play.google.com/store/apps/details?id=com.keuwl.spectrumanalyzer

PC app: http://www.ymec.com/products/dssf3e/ " DSSF3 Light RA + Mmlib" version 

[201er]

I can say first hand that the custom mold ear plugs for Halo aren’t any quieter than the foam tips. However, the foam tips lose their sound blocking rather quickly after a few uses. So if you don’t replace them in time, they do get noisy. Whereas the custom mold plugs last for years.

[dkkim73]

5 hours ago, A64Pilot said:

Here’s the thing about ANR, it only works between 50 and 300 Hz frequencies that are annoying and any noise causes fatigue, but the frequencies that ANR blocks isn’t really very damaging, high frequencies cause the greatest hearing loss. So headsets that are poor passive headsets and rely heavily on ANR aren’t very good at protecting from hearing loss, you need to block the high frequencies.

^this

This is what I was getting at by saying have at least one layer of passive. 

[midlifeflyer]

10 hours ago, 201er said:

I can say first hand that the custom mold ear plugs for Halo aren’t any quieter than the foam tips. However, the foam tips lose their sound blocking rather quickly after a few uses. So if you don’t replace them in time, they do get noisy. Whereas the custom mold plugs last for years.

Yeah, the 3M yellow foam tips are really intended for single use. OTOH they’re really cheap. I have some but they are for demos.

[RoundTwo]

21 hours ago, LANCECASPER said:

Whichever of the in-ear models allow you to use molds to get earplugs for your own ears (perhaps made through an audiologist's office) might be the best way to reduce noise where it counts - the noise which is allowed to enter into your ears.

Another place to get molded silicone ear plugs is pretty much any motorcycle rally or shooting match. There are normally booths setup and they can do them on the spot for $65 - $75. I got my last pair at a Glock match, but any decent sized USPSA or IDPA match should have them because there are always unprepared spectators that attend.

[RoundTwo]

I think I’m going to try “double plugging” with foamies under my ANR headset for our next long flight. After 6+ hours yesterday, coming home from MooneyMax, my tinnitus has kicked up a notch or two, and that can’t be good.

[Hank]

11 hours ago, 201er said:

I can say first hand that the custom mold ear plugs for Halo aren’t any quieter than the foam tips. However, the foam tips lose their sound blocking rather quickly after a few uses. So if you don’t replace them in time, they do get noisy. Whereas the custom mold plugs last for years.

I don't like foam ear olugs--they're hit in the summer, hard in the winter, and if you roll too much taper they ooze out if your ear.

Fortunately Halos ship with several different silicone tips, and I really like one of them. They last for years, and replacements are $3/pair.

My wife didn't want an in-ear headset, sticking with Dacid Clark 13.4's until I bought a set of Halos for her to try, because I could resell then easily. Only took 20 minutes to change her mind. "Try it, you'll like it."

[A64Pilot]

1 hour ago, midlifeflyer said:

Yeah, the 3M yellow foam tips are really intended for single use. OTOH they’re really cheap. I have some but they are for demos.

They are meant for single use, but in the Military we always put the foamy ear plugs in the little pocket on the left arm of out flight suit, the plugs sort of got washed whenever the suit was and flying every day I only went through one or two sets a week.

Most often what has you throwing a set away is when they get so much ear wax on them that you don’t want to put that thing in your ear, but they would still work.

Army issued reusable rubber type ear plugs, we had to wear the little box containing them on our BDU uniform. I hated those things after an hour or two the gave me ear aches. I never wore them.

The most comfortable ones I ever wore were the custom ones, they were actually pretty hard, but as they fit perfectly they were comfortable. They came with a little tube of white cream that you used to lube them up to put them in, but over time you learned that you could get them just a tiny bit wet with your mouth and they would pop in, but dry would be tough, they sort of rotated for some reason on insertion. You could comfortably wear them all day and I often did.

‘If your concerned about hearing loss don’t pop $1000 on Bose headsets, they really don’t do much, instead buy the ear plugs made by the Audioologist.

Edited September 9 by A64Pilot

[A64Pilot]

39 minutes ago, RoundTwo said:

I think I’m going to try “double plugging” with foamies under my ANR headset for our next long flight. After 6+ hours yesterday, coming home from MooneyMax, my tinnitus has kicked up a notch or two, and that can’t be good.

It’s not, years ago the Dr that gave us the class on hearing loss that told us about the radio being loud in the morning told us that the reason why was the little hairs in our inner ear that sound moves to make us hear get knocked flat if you will by loud noise so our hearing is impaired temporarily. Over night they don’t experience any loud noises while we sleep and they stand back up, that’s why the radio in the car is too loud in the morning, but also tinnitus can be caused by these hairs being knocked down. That’s why our ears “ring” from experiencing really loud noises like gun fire, explosions etc.

Hearing loss comes from these hairs being knocked down so often that they just stay down eventually, and honestly age plays into it as well, often old people who never experienced loud noises get hearing loss but of course loud noise exposure makes it worse, so you young guys are wearing hearing protection now so one day you can hear your Grandkids.

Edited September 9 by A64Pilot

[RoundTwo]

I use foamies to sleep every night and have found the 3M E.A.Rsoft^™ Yellow Neon Blasts^™ Earplugs work best for me because they are low-bulk and don’t exert too much pressure in the ear canal. In a pinch, I’ve tried others, but sometimes there’s just too much inner-canal pressure to be comfortable for sleep. The Neon Blasts are smooth on the outside and don’t collect contaminants like the open cell classics that used to come in the cardboard pillow boxes. If they inadvertently go through the wash, they’re still usable, but they’re just more difficult to insert before they rebound to original shape.

[RoundTwo]

7 minutes ago, A64Pilot said:

It’s not, years ago the Dr that gave us the class on hearing loss that told us about the radio being loud in the morning told us that the reason why was the little hairs in our inner ear that sound moves to make us hear get knocked flat if you will by loud noise so our hearing is impaired temporarily. Over night they don’t experience any loud noises while we sleep and they stand back up, that’s why the radio in the car is too loud in the morning, but also tinnitus can be caused by these hairs being knocked down. That’s why our ears “ring” from experiencing really loud noises like gun fire, explosions etc.

Hearing loss comes from these hairs being knocked down so often that they just stay down eventually, and honestly age plays into it as well, often old people who never experienced loud noises get hearing loss but of course loud noise exposure makes it worse, so you young guys are wearing hearing protection now so one day you can hear your Grandkids.

My problem is that those little hairs that start out on the inside have decided to leave town and have all moved to the outside. Now they’re all grown up and are thick and curly. 

[GeeBee]

When I was having my interior redone, I thought about re-doing the sound insulation then I thought, "No matter how much and how good you use, you're still going to wear an ANR headset anyway". So I kept the stock insulation because it is a losing battle in a recap. There is only one airplane I ever flew that I could fly without a headset and that was the Airbus. Even Boeings are too noisy. 

[Pinecone]

Decibels are a logarithmic scale.  So a 3 dB reduction means cutting the sound power in half.  So even a 1 or 2 eB reduction helps.

The best hearing protection is good foam plugs like the Howard Leight Max plugs with about 33 dB NRR.  Combining plugs and passive headset gives you about a 5 dB greater protection than the higher NRR.  So with a headset and plugs, about 38 dB.

The apps are nice, but without a certified mic, they are not accurate.  But they do tend to be precise, so you can use the same app on the same phone to compare before an after, but you cannot compare your numbers with my numbers.  My old iPhone 3GS was within a 1/2 dB of lab quality sound level meters.  My iPhone 5 was more than 3 dB off.

[Fly Boomer]

The way I can tell that my foam plugs need to be replaced is when I can't get them inserted properly before they expand too much.  When new, they expand very little between the "rolling" stage and the "inserting" stage.

[BlueSky247]

Lifelong hearing aid wearer here...

 

I'll second/third the custom earplugs recommendation, but make sure they are of a soft material. You do not want the lucite/acrylic ones - those end up being painful under extended wearing.

 

@Schllc It sounds like you might be able to use some programmable hearing aids for flying. The idea being you'd get just a little bit of boost in the voice regions and the selective frequency programming along with the passive reduction in the ear plugs, would help with the background noise.  Use those with a decent ANR headset and you'll feel like you are on the ground, idling.  That's essentially what I'm doing and it works very well. 

 

[Pinecone]

21 minutes ago, Fly Boomer said:

The way I can tell that my foam plugs need to be replaced is when I can't get them inserted properly before they expand too much.  When new, they expand very little between the "rolling" stage and the "inserting" stage.

That can also depend on the plug. The classic E.A.R. plug expands slowly.  Others are faster.

[LANCECASPER]

I know the first post started out with "Aside from a tight door seal, are there any real ways to reduce the decibel level in the Mooney?", however that's still where the vast majority of the noise is coming from.

On my last airplane I painstakingly put in a Bob Fields Inflatable Door Deal and, once I did some test flights and adjusted it a few times, it was the quietest piston airplane I've ever been in. One caveat - I don't know of a shop that would be willing to spend as much time as I did getting it right, or any owner including myself that would have been willing to pay a shop that many hours to get it right. I could actually have a conversation without a headset. Had I kept that airplane the next project would have been improving the baggage door deal. 

[midlifeflyer]

2 hours ago, A64Pilot said:

They are meant for single use, but in the Military we always put the foamy ear plugs in the little pocket on the left arm of out flight suit, the plugs sort of got washed whenever the suit was and flying every day I only went through one or two sets a week.

Of course. "Meant for single use" doesn't mean they don't last longer. Just that they were designed for audiologists doing hearing tests - one to a customer and toss. 

[wombat]

2 hours ago, LANCECASPER said:

I know the first post started out with "Aside from a tight door seal, are there any real ways to reduce the decibel level in the Mooney?", however that's still where the vast majority of the noise is coming from.

On my last airplane I painstakingly put in a Bob Fields Inflatable Door Deal and, once I did some test flights and adjusted it a few times, it was the quietest piston airplane I've ever been in. One caveat - I don't know of a shop that would be willing to spend as much time as I did getting it right, or any owner including myself that would have been willing to pay a shop that many hours to get it right. I could actually have a conversation without a headset. Had I kept that airplane the next project would have been improving the baggage door deal. 

Can you tell us more about the painstaking part of it?    On my non-inflatable one, I glued it in, and that was kind of it.    Not really possible to do much adjustment easily.

 

[LANCECASPER]

1 hour ago, wombat said:

Can you tell us more about the painstaking part of it?    On my non-inflatable one, I glued it in, and that was kind of it.    Not really possible to do much adjustment easily.

 

Gluing it in once and getting it right the first time is not going to happen with most doors since each of them are a little different. I used RTV107 so that I could peel it back and adjust it after I went up and test flew it to see where it was still leaking. That's the product that came with the Bob Fields Seal. But probably best not to turn this into a door seal thread - my apologies - since he's looking for ideas other than the door seal. 

There has been a lot written about this:https://mooneyspace.com/search/?q="inflatable door seal"&quick=1&updated_after=any&sortby=relevancy&search_and_or=or

 

[AJ88V]

I've wondered if most of the noise comes from the pressure pulses off the prop coming back and hitting the windshield which re-radiates the noise. 

Pressing on the windshield from the inside seems to reduce the noise, but it's hard to tell while flying since you're changing your head position relative to the cockpit.  Maybe get a passenger to press on the windshield while you fly?

If you could find a sweet spot, maybe you could place a support/damping rod between the center post and the windshield.  Anybody try this?