Earthstar Forums

Now that is a cool noise suppression idea, cheap pillow from Walmart and stuffed into the back. I bought some 2" foam with the egg container looking bumps all over it, and cut a chunk to fit into the back hole. It does help, and I need to finish trimming it to fit better. I agree, reduce the inside sound level first, then go for the best headsets. I still use my 25yr old Clark's, and can't afford $750 for the Telex.

kb

I fly with the Bose aviation headsets. When i turn on the noise canceling switch it's so quiet, I'm just amazed. They are so soft and light one the head And ears, I flew from Ohio to NY and they didn't bother me at all. At Oshkosh they have a large display and you can try them in a noise environment they setup. Try a few times on eBay and you can find them for half price.

Search Bose aviation x

Gary

Gary,

I presume you are flying an Earthstar aircraft (because of the name of this site).

I concur the Bose was the very best for a lot of situations, especially in aircraft that are not extremely loud as the Luscombe I have now. I had many years of quality use in my old Cessna 150 and 172 before I moved over my current noisy old aluminum plane. The Bose microphone wouldn't work well in the higher noise environment and I was also concerned that if I ever ran out of electric power the active part of the ANR system would leave me with a somewhat thin and delicate set of ear cups. The Telex 50D I am using now in my high noise environment has a very cushy set of ear seals (passive NR) as well as the electronic (active NR) noise cancelling part to make a good combination for me. The microphone on the Telex still is not optimum but it is the best I've tried so far. Another aid to microphone noise pickup is the addition of a foam mic cover with a little leather "jacket" tied over it with a voice hole pointing towards my lips and an opposite hole pointing forward, to help cut out some of the massive ambient noise. I get pretty good side tone as well as clear enough transmissions (as confirmed by some of my flying buddies).

The conclusion I have from reading the posts on the Earthstar headsets is that they (Earthstar Aircraft) are apparently pretty quiet (as aircraft go....with an engine nearby your ears).

Skot

Skot

I do use them in my Odyssey and haven't used them in any other plane.
The clarity is excellent. The mic works excellent also.

I'm not sure our airplanes are all that quiet, perhaps the 4-cycles are more
so.

Dave Bonkowski's airplane is 112 db (A scale) at cruise at his head position
(he has no bulkhead between him and the rear of the airplane). Mine is
about 100 db at cruise. I have a bulkhead between my cockpit and the engine
area plus a fair amount of sound absorbing foam. Both Dave and I have 2
cycle engines. This is one of the big disadvantages of of the "view your
gas tank" method since there is no bulkhead to absorb sounds between you and
your engine. Mark recommends putting sound foam (or lots of pillows) on the
rear section of the aircraft where sound from the prop and engine can come
inside. According to Mark, a 4" hole defeats the entire purpose of sound
proofing, so all the holes in my airplane's rear section are sound proofed
(including the fingers holding the control wires) and the hole where the
push rod goes to the aileron control rod in the wing. I have sound proofing
along the top of the cockpit (bottom of the wing). Anyplace where you can
feel vibration is a place pushing noise into your cockpit. A lot of noise
comes through the windows of my JT2. This is unavoidable without going to a
really thick Plexiglas and I'm not willing to add the weight. When I did a
dynamic balance of my prop and used the softest possible rubber (for engine
mounts) for my engine weight and HP, the engine vibration decreased enough
that much of the window vibration went away. My engine is now smoother than
many 4-cycles (the Hirth 3701 is a 3 cylinder 2-cycle, and that # of
cylinders is know to be smooth in a 2-cycle).

My next improvement will be to fill the wing gap on the right side of my
airplane where a fair amount of noise is coming from the intake of the two
cycle engine. The left side is filled with my air duct for the radiator.
My intake isn't as noisy as a 503 since I have reed valves, but the right
side of the aircraft is noticeable noisier than the left. I'll build a
shape matching the flap out of aluminum and will fill that with 2-part
expanding foam.

I've been researching headsets and there appear to be two at the top and
roughly comparable. The Bose A20 (replacement for the X) and the Lightspeed
Zulu. The Bose might be a smidge better in ANR, the Zulu handles glasses
better and is several hundred dollars cheaper. The Zulu now has two
flavors, the New Zulu and the Original Zulu. Reviewers can notice little
difference between the two Zulus except the new Zulu has less clamping
pressure, but according to the factory the ANR is slightly better, as is the
music sound, and the Mike is a new design that gives slightly more clarity.
Zulu dropped the price of the Original by $50 bucks and will be phasing them
out.

I just bought one of the Original Zulus, mainly because I can use the trade
up program to pay a substantial part of the cost. The new Zulu trade up
program won't start until Sept. and summer is awaiting.

I have to admit I love my (Original Zulus) and am using them at work to
listen to music and reduce noise while I work as well as to answer and talk
through my phone (the Zulus have a Bluetooth connection that works well with
my iPhone). The Bluetooth sucks down more power and Zulu recommends turning
it off when not in use (i.e., when flying at 7000 ft.). But if that becomes
a problem at work I will just use rechargeable batteries on the ground.

I have found that the Zulus are quieter in my airplane and much more
comfortable than my top level Sennhesiers. I can wear then for hours
without a headache. Being able to make phone calls from my airplane (while
taxiing, of course) is a big advantage. With the higher quality Mike and
electronics my radio output and input is noticeable higher fidelity.

My big beef is that unlike the Senheisers I do not have a way of supplying
the headset ANR with aircraft power, at least while keeping the two GA plug
version. There is a 7pin LEMO version, but that version does not allow you
to convert the LEMO to a two plug GA + battery version for use in a friend's
airplane. I may come up with a 12 volt to 3 volt voltage regulator that can
be designed to fit into the battery compartment of the Zulu and replace the
batteries. Not hard to do, just takes time.

Oh yes, the Zulu sound output can get painfully high. They have a two
slider setup which regulates the sound output but the slider moves easily
and at higher gains the output is so loud you can damage your ears (as I
found out when I accidently slid the slider up to about mid-point). I fixed
that by putting tap in place that makes it impossible to slide the sliders
past about 3 markings. When I called them about this to see if they had a
way to reduce the gain, the gave me the "we've sold 80,000 of these units
and you are the first to ever call us about this problem", yeah right. They
aint going to help and my previously very high opinion of their support went
down a notch (this is the second lightspeed headset I've owned and they
really came through when my last one broke). I may set up a voltage divider
in my intercom input to reduce the volume. Perhaps my radio has a setting
to reduce the overall gain (other than the volume control).

Also, replace the foam seals every 18 months or less of any headset. There
is enough degradation in that time to adversely affect the seal.

-Alan

That's a wonderful posting Alan. Lots of detail that should be of help to anyone
shopping for a headset.

I'd like to know more about how you changed the rubber for your engine mounts.
Supply sources, specs for engine weight and HP, etc. I'm sure my 503 has
inherently more vibration than your Hirth. I'd like to reduce vibration in the
cockpit to improve the quality of my Contour HD videos. I've built in some foam
damping in my home-made three-point camcorder mount, but I just used material I
had handy (from an old foam back packing pad). It needs to be replaced with
something more substantial, yet soft.
 Dick O'Reilly

Folks,

Does anyone have any experience with the "in your ear" setup like the
Clarity Aloft?

It appears to have no ANR technology and depends on the ear seals at the
end of the tubes that go into your ears. I have been watching them on EBay
and they always go for a lot of money. I have also tried them out at
Oshkosh but the conclusive evidence I'm looking for is a testimonial or by
actually using one.

Skot

P.S. Dave and I used a sound level meter from Radio Shack to do our measurements. About 40 bucks.

-Alan Cossitt

>From my iPhone. Please excuse typos and terseness.

I have Lord style engine mounts. On 503 engines you can pretty much use red
(soft) lord/Barry mounts. The best source that I have found (so far) is CPS
(1-800-AIRWOLF). They sell Barry mounts which are a little stiffer and
perhaps higher quality than the Lord mounts (same dimensions etc.).
Aircraft spruce sells the Lord mounts which I think are slightly softer and
may be better for 503 but they charge a lot more per mount.

In my aircraft I use yellow (medium) where ever the torque or thrust of the
engine is greatest. Everyplace else I use red (soft). So if your thrust
and torque is pushing down, I use a yellow below that (the push presses on
the yellow) and red above.

these styles of headset work best with custom ear inserts. These are cast
by a professional from the actual shape of the ear canal and then the
manufacturer generates the actual piece. Noise reduction between the
default and custom earpiece is substantial. I believe Lightspeed has
information on the difference for their version. But this will cost you a
couple hundred bucks.

This means that you probably won't be able to sell them later unless you
keep the default earplug.

The key is to keep the noise the ear hears down below 85 dB. At or above
this you must start limiting your exposure. I believe that at 85 you must
limit to 8 hours or less per day (don't quote me since this is from memory
and may be wrong or out of date). So, in my airplane if the environment has
a 100 dB noise signal and my head sets reduce 25-30 db, I'll be hearing
70-75 dB. Also keep in mind that the dB you hear during radio transmissions
is going to be higher than this baseline. So your chatty buddy you fly with
may be causing you ear damage. In cruise I keep my radio turned as low as
possible. If I'm by myself I'll switch it to the emergency frequency and
listen for ELTs and folks in trouble. Usually nice and quiet. Ditto for
the intercom. The lower the sound baseline the lower you can keep your
radio/intercom setting and the less hearing problems you'll have.

That is also why I don't listen to music in flight. Needs to be too loud to
hear it. Not worth it. Now, if my airplane was 80 dB, things would be
different. If my airplane was 110 db, my baseline would be 90-95 dB. At
that point I would consider putting in in-the-ear earplugs in addition to my
headset during cruise to reduce ear damage.

-A