DIY Headset Microphone

This has been on my mind as well. I think the JLI is a bit large for this specific application - personally I'd use something like a Primo EM272Z1 as it's much smaller and sounds nice for such an application. I wouldn't worry too much about sound transmission through the arm as if it's attached to headphones it'll be somewhat isolated from any keyboard noises etc. Have you seen how I did it in this video? 7:33 timestamp.

I'd agree with Matt on this one.

However if you have the funds and can wait for a few weeks, we have an excellent design for a really lightweight mic assembly with full screening and a direct analogue out based on a MEMS mic that's actually intended for this sort of application.

The board is currently laid out for a 26mm application (it's part of my new designs) it's easily shrunk down to as little as 10mm square or less. I'll do something later today in fact and put it on my GitHub.

This device is a bit out an outlier since it only needs a 2.7V supply (yup, it's a bit weird but easy to power).

Using an old laptop mic is certainly a lot less hassle, even if it's not as pretty. 😉

Hi @LudaBago

Hi @ludabago, I did some of those MEMS mic heads if you're interested, including a some variations that give line level output at 5V but have an on-board regulator so you don't have to worry about gnarly supply lines. They also glow a beautiful green when turned on so they look great. 

I haven't uploaded the design to GitHub yet but they are ready and work treat although (and this might matter) they're omnidirectional unlike the Primo that Matt's mentioned which I think is a cardioid which is more suitable for voice due to the directivity.

There are two here, a stereo pair but you split them down the middle, and deliver mic level output but the quality of the screen on the MEMS devices is such that they are almost completely unaffected by extraneous noise (EMI). 

It's a very simple PCB design and there's lots of free space that can be discarded. I give them names so I can keep a track of which is which quickly and easily but for short runs - JLC will populate two full boards for you which is four sets in total so they're cheaper than a cup of Barista-drawn coffee.

Making a boom mic from these is trivial - this is only a dummy but it's largely a case of changing the board outline to suit your needs. I would be tempted to cut this boom into two parts and put a solder bridge in the middle. Note that the socket here is for 2.54mm pitch, but it's trivial to switch that to a 1.25 mm (1/20th inch) pitch if you're up for soldering that. SMD pins are quite costly unfortunately so I tend to recommend the 2.54 mm for easy of use.

@diyperks

I don't know if this is useful but I can easily make a version of this with the 3-5V amplifier section at the far end so it will output up to around 600mV which is more than enough to drive a line input on a digitiser of your choice or plug directly into the line in of a typical recorder. 

The boom can be up to 100m long with a head measuring 10 x 5 mm. The amp can be separate or built as part of the boom itself. Or, if you want to be REALLY flash, JLC do fully flexible PCB for about $15 (the FR4 is just $2 for the same size) but once you add in the parts and shipping there's not a lot of difference.

@marcdraco 

This is exactly the direction I needed for this protect. I am so happy I found this forum, somewhere where people are willing to go over the top on a problem. I have been looking around for a smaller mic but I do want to preserve the unidirectional nature of the mic. In addition to using this for recreation, I do a lot of dictation in crowded rooms that can have a lot of background noise. The nicer quality microphones work so much nicer when it is quiet but the only directional mic they have available does not have the quality to make it very useful.  I am just getting into the audio portion of electronics and the DIYperks forum has been invaluable. Thanks!

I'll drop some proper CAD files and a project just as soon as I complete the current one. I'm a little behind at the moment but the latest changes apply to everything so it's just a case of moving the edge cuts to make a little 4" boom. 

A gremlin bit me on the headphone amplifier section on the last set so I've swapped out the section for an IC solution rather than a bespoke one based on a low-end op amp.

This is some WIP on the new set of mic heads. The last lot work as expected but I saw some areas o for improvement, esp. this one:

Admittedly this isn't something I've tried before but here goes. The cut-out area allows this mic to work in two "modes". In the "normal" mode it will behave exactly like all the other mics on this pack but if you *carefully* punch out the 8mm circle there are breakout pads for the three connectors on the MEMs IC.

Some care is going to be needed because things are really tight in order to keep a push-out piece so small. The final version has a "special" capacitor placed right up against the chip.

Also - these devices are designed to run at 3.6V absolute max. The board has an LED "regulator" for this but the cut down one doesn't so you'll still need that. Of course, the power can be tapped from the 26mm section if that's mounted elsewhere.