Sunday, 10 January 2010
DIY Binaural Mics
My good friend Lungwah regularly uses in ear binaural mics and I've always dug the sound he achieves in his field recordings. Having recently got a boss micro br portable 4track recorder I wanted to not only use it as a 4track but, as it can record straight to wav or mp3, as a field recorder too.
So I've made my own binaural mics...its a really simple job. I found a couple of electret mic elements (I had a pair in one of my many scraps boxes but you could buy them here for example) and an old pair of earbuds that are large enough to house the mic elements. Simply crack the earbud cases open, desolder the headphone elements, work out which wire is signal and which is ground and then solder in your mic elements.
Most electret mic elements have 2 solder blobs on the back, one for ground and one for signal, the way to tell which is which is that the ground contact will have a trace going out to the case of the element. If you click the link above these are visible on the picture.
The earbuds I used had a small vent from inside to the exterior of the case anyway but I made it bigger to expose more of the mic element, you can see this in the picture just above the classy gold bands! I then used a spot of hot glue to hold the elements in place and reaassembled the earbud cases. I was done in about 10 minutes.
I'm pleased with the sound results from these and enjoy the fact that you can be doing a field recording and yet not draw any attention as you are only wearing earbuds....which happily had a L and R on them so I even manage to get them in the right ear!
I was asked in comments to upload a sample recording...here we are
It's not the wildest thing I've ever uploaded, it's me just walking for a couple of minutes from my office door into town..highlights include, a pram wheeling beside me, cars passing, a phone ringing in a garage and some seagulls! It's recorded on the hifi (compressed setting) on the micro br, then exported on the unit as a mp3 transferred to computer for trimming and converting into wav (for bandcamp). I think you get a good idea of the soundscape if you listen to this through headphones.