In-ear headset - rolling your own cheap and easy

cnpeters · Post by **cnpeters** » Mon Aug 27, 2007 10:43 pm

I made an -in ear headset for $70 in 5 hours. I tested it flying last night for 1.5 hours after some ground checks - worked perfectly, with good external sound attenuation. Here is my write-up with pics on VAF:
http://www.vansairforce.com/community/s ... hp?t=20917
Fire away if any questions,
Carl

smittysrv · Post by **smittysrv** » Tue Aug 28, 2007 8:19 am

Very cool! I have an old stereo headset that's been sitting in a drawer for years. I going to rip it apart this afternoon and get started on my own in-ear headet.

svanarts · Post by **svanarts** » Wed Aug 29, 2007 12:13 am

Very cool. My RV-4 is REALLY loud. I'm just not sure these would cut down the noise enough for me.

cnpeters · Post by **cnpeters** » Wed Aug 29, 2007 12:58 pm

Comply now makes a headset (NR-10) that promises even more dB attenuation and comes with an inline volume control for $60. I recall someone comparing the NR-1's I have to the Bose X ANR's and said they were equal, but after my recent testing against one of the quietest passive cupped sets (Lightspeed QFC) I'm not sure. They were at least AS quiet and maybe a little more than the QFC, but I am working on getting together with Chad and comparing to his halo and an ANR cupped set at the airport. I really would like to compare against something pricey like the Bose - I'm willing to bet I will get as good a musical quality (thru XM) and within 90% of the noise attenuation at cruise. All for less than 8% the cost!!
http://www.magellans.com/store/Applianc ... F102?Args=

TomC · Post by **TomC** » Wed Aug 29, 2007 6:47 pm

Hi Carl,

I just purchased a set of NR-10's from Harris Communication at

http://www.harriscomm.com/catalog/advan ... ords=nr-10

The cost was $59.95 + $8.00 s/h. I am very interested to see how well they work. I have few questions about making them into an aviation headset. I don't have an old headset and was wondering if there is a source for a mic. On your system, you use the circuit board from an old headset. Is this a requirement? If I adapted the NR-10 cord to the standard aviation headset plug, would they work with no other circuit? I am in no way an electronics tech. Any advice would be appreciated.

Thanks for the ideas.

cnpeters · Post by **cnpeters** » Thu Aug 30, 2007 12:14 am

I am curious on your thoughts of the NR10 when it comes in. Perhaps you could use it with an mp3 player at ATC voice volume while running up a plane to see it's attenuation for now until you build your set.
The earpieces can be wired directly to the headset cord. Up to you. I like the separate 1/8" jack so I can bring my headset home with me and use it for other things. There are two headset wires coming from the plug, one is the mono channel (on mine) and the other a ground. There was an extra clipped wire that may be the other channel for a stereo headset - sometimes cheaper to use the same cord for all your headsets sold and just not use some of the conductors on the cheaper mono sets like mine. The headset plug is stereo, so all I need to do is disconnect my left and right channel jumper on the 1/8" jack, and connect the clipped wirefrom the cord that is hanging in the breeze within the project box (after testing continuity with the plug to doublecheck).
The headsets will likely be louder at a given volume than a regular cupped headset, but the inline volume will make that moot. Without this, you will need to add transformers (one of mono) or potentiometers to better match the intercom output with your headset. Read the links (not Pete Howell's) I posted to see what I mean. No thanks, much more complicated.
The mic is what has the circuitry - it was a simple 1/2" wafer from my simple AvComms - I found it in one of the cups and carefully traced the wires (a red and white coming in, another pair exiting), wrote down the orientation, and just transplanted it "upstream" in the project box. The mic wires just come into the box from the mic plug, attach to the chip, then exit thru the other end of the box and go to the wire frame. I wouldn't exclude this circuit - not sure what it has (noise filters?), but it was no big deal cutting it out of the mic cord in the cup and moving into the projectbox.
If you don't have a headset to gut, I recommend an inexpensive one off ebay. You will get the mic, circuit, plugs, cords, and cord strain relievers (for a more polished look). If you read some of the links I posted, there are other links mentioned that get into buying a cheapie mic from Radio Shack, but then you have to figure out the circuits if needed, flox up a housing (and remember, many mics need openings above and under), buy plugs and cord (only cord I needed extra was the thin 2 conductor one from the box to the wire frame and mic - you want something thin, and can use on of the wires from an stereo RCA plug patch cord or any other item that uses a small wire).
Hope this helps, and let me know if you have more questions.

TomC wrote:Hi Carl,

I just purchased a set of NR-10's from Harris Communication at

http://www.harriscomm.com/catalog/advan ... ords=nr-10

The cost was $59.95 + $8.00 s/h. I am very interested to see how well they work. I have few questions about making them into an aviation headset. I don't have an old headset and was wondering if there is a source for a mic. On your system, you use the circuit board from an old headset. Is this a requirement? If I adapted the NR-10 cord to the standard aviation headset plug, would they work with no other circuit? I am in no way an electronics tech. Any advice would be appreciated.

Thanks for the ideas.

smittysrv · Post by **smittysrv** » Thu Aug 30, 2007 7:15 am

I went out to the hangar yesterday and found a 10 year old stereo headset that was replaced by a newer model long ago. I felt like a kid again riping it apart. I salvaged the rubber grommets and the volume control and drew out a schematic of the original wiring before taking the electrical harness apart. I went to Fry's electronics and bought some long heat shrink rubber tubing and nothing else, mainly because they didn't have any of the other stuff I was looking for! Unbelieveable!

Next stop, Radio Shack. They have it all. I bought a project box:
http://www.radioshack.com/product/index ... age=search

A 1/8" Stereo Panel Mount Jack:
http://www.radioshack.com/product/index ... age=search

A bag of assorted Grommets:
http://www.radioshack.com/product/index ... age=search

And a 6 foot stereo cable with two plastic coated wires and a shield for the mike.

Got my smarts from Wikepedia: (since I don't know Jack about Jacks)
http://en.wikipedia.org/wiki/Jack_plug

I am going today to Target to get these battery powered noise cancellation earphones. I have a friend who rides Harleys and swears by them:
http://www.target.com/gp/detail.html/re ... B000G36GOU
UPDATE: 8/30/2007 - I bought these earphones today and they ain't so hot. Dang it!
UPDATE: 9/7/2007 - Forget the previous update. I got everything put together today and tried the whole setup today in my C172. WOW, when I turned on the noise reduction is really cut the volume considerably.

Here's my progress so far. I will make the neckpiece this afternoon and connect the mic:

TomC · Post by **TomC** » Thu Aug 30, 2007 12:05 pm

Carl,

I should receive the NR-10's shortly. I will see how they work in the noisy plane, hopefully this weekend, and post my opinion. Would this be a possible microphone?

http://www.radioshack.com/product/index ... ab=summary

I might get one and try it out. If it doesn't work, I can always return it. It says it needs a watch battery. If this is correct, it would not be the way to go.

I'm having so much fun designing something I know nothing about.

cnpeters · Post by **cnpeters** » Thu Aug 30, 2007 10:59 pm

It may work, but I don't know how the unit will match with the intercom. I guess you could regulate the mic volume on your intercom, assuming you have that feature. Otherwise, I wouldn't touch it. The other negative is the battery, likely to amplify the weak mic output. I wouldn't mess with it, but hey, experimenting can be fun.
Smitty - nice setup. Let us know how it works... .
Carl