BINAURAL MICROPHONE – DUMMY HEAD DIY V2
Advanced version and improved case strength of the Binaural Mic DUMMY Head.
Binaural recording is a method of recording sound that uses two microphones, arranged with the intent to create a 3-D stereo sound sensation for the listener of actually being in the place where it was recorded.
This effect is often created using a technique known as “Dummy head recording“, wherein a mannequin head is outfitted with a microphone in each ear.
Binaural recording is intended for replay using headphones and will not translate properly over stereo speakers.
If you plan to use the Binaural Dummy head for measuring exactly how the human eardrum would receive sound, you need to use an ear canal, as your goal is to “measure” what is arriving to the eardrum.
Bur for playback of binaural audio recordings, which is the most typical situation, the capsules must be placed in the exact location where the headphone will be.
The reason for this is that, if the capsule is placed inside an ear canal, when you playback those sounds trough headphones, the sound will have to travel from the Speaker to your eardrum once more… causing “tube” effect and unwanted frequency response.
Silicone human ear models for Binaural Recording:
One of the hardest steps in the whole project was the Silicone Human ear models. Is not as easy as I thought at first to get proper “anatomically correct” model. I struggled nearly a month to find a source for proper silicone models trough my brother, which is a Biologist and he managed to guide me in the right direction to get my first pair.
They were expensive and I wanted to continue building new Binaural microphones, so the solution would be to “clone” this original molds. For this task I also got the help of my brother and father which are extreme DIY enthusiast. My brother loves Roll games, and started doing his own miniatures a long time ago, he started cloning this originals using a Custom made vacuum chamber which allows bubbles to disappear when making molds. Amazing stuff.
So with this components and a bit of messing around, we finally managed to get good results. We have made a first batch testing different consistencies, ways of coloring, trying different shapes for the base… The next test will be made using a slighty softer silicone but the final mold is done.
I will be providing trough the shop this Silicone human ear models for anyone interested.
Why is important an “anatomically correct” human ear model?
Function of the Pinna or Auricula:
The function of the pinna is to collect sound, and perform spectral transformations to incoming sounds which enable the process of vertical localization to take place.It collects sound by acting as a funnel, amplifying the sound and directing it to the auditory canal. While reflecting from the pinna, sound also goes through a filtering process, as well as frequency dependent amplitude modulation which adds directional information to the sound (see sound localization, vertical sound localization, head-related transfer function, pinna notch). The filtering effect of the human pinna preferentially selects sounds in the frequency range of human speech.
Binaural recording Audio-video test using WindShields :