Binaural Microphone – Dummy head

What is Binaural Recording:

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 room with the performers or instruments. 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.

Maledictis DIY – Binaural head rocks.

Well,  so this is the latest creation in the Maledictis DIY section and one of the most exciting DIY projects I´ve ever done… I allways wanted a dummy head like Neuman´s, since I saw it and heard it… but allways thought it was a project which it will be never achieved unless I had the few grands you need to get one comercial Dummy head.

My design is not a 100% head, but 2 anatomic human ears built in ear canal (silicon), adapted in a chasis… as I dont want to be carrying with a head around :).

I  added a tripod mount screw on top, so I can adapt my camera and record video at the same time, as this is one of the best ways to increase the 3D localization of elements.

This project felt like a big achievement because it was a hard task at times. I faced many problems with  the case design, finding the right ears and ear canals… also modifying the mic capsules (5mm diameter) as suggested in Linkwitz site…  but once it was plugged and I realised how good it sounded… the smile in my face was like…

Binaural recording and listening has always had it’s limitations. The biggest problem has always been that everybody’s ears are different shapes, their heads and torsos are different sizes, etc… This physical difference we all share has basically been accepted as an impossible hurdle to overcome for binaural. It is physically impossible to build a single binaural recording device, dummy head or microphone, which will satisfy every person equally.

The result caused by these physical differences is front/back and up/down localization confusion. This is less obvious when you incorporate video. A subjetive view from the listeners position will enhace the experience telling your brain new clues regarding how to listen trough this new pair of ears. The visual feedback basically teches your brain the new format of the directional sound coming to your head.

The interesting thing here is that once you’ve learned the new format, you don’t necessarily need the video to hear things properly and accurately anymore.

So I recently came across the need of bulding a normal omnidirectional mic for sound treatment, and found online very usefull information. Most of the projects needed a modification in the capsules in order to work at reasonable SPL levels without distorting, the mod can be found here in Siegfried Linkwitz.

I used some tools to help me hold the capsule and cut it… then solder two leads to it… some stressfull momments here…

One of the side projects I found was this, binaural recordingusing exactly the same capsules… so here we go!!

The capsules ar tiny, they have 2 pads.one of the is conected to the shield. So we have to cut the trace that is joining the pad to the chasis of the mic capsule and then solder the other pad to the shield.

So basically it is a stereo microphone set, with its own phantom supply voltage, so it can be pluged anywhere… Minidiscs, handy recorders, mixers, everything… It uses a 9 volt battery that should last a few years…

The whole science behind this is pretty amazing, it hapens the same than 3D image… Once your brain gets that information, it decodes it as if it was reallity, giving you deph impresion or in this case, 3D sound sensation…

By using 2 anatomically correct silicon human ear models, bulding an ear canals of 3cm (like real one) and adapting on them an omnidireccional microphone…  we will get a very close 3D sensation… it is definitely much much much better than a normal stereo setup as the sound is complitely surround.

Check the videos for sound tests…

Video 1: First Test.

Video 2: Rainy day test.

Video 3: Traffic test.

If you are interested in purchasing one or you need any more information do not hestitate in contacting me trough the contact section.

Hope you enjoy it!