Binaural In-Ear Head Worn Stealth Microphones

Ideal for Low Profile Field Recordists or Concert Tapers

Apr 26, 2009

A microphone in the open makes a visual statement, not always ideal. Binaural mics look just like in-ear headphones, reducing impact for field and urban recording.

Most people expect a microphone to look like a typical dynamic vocal microphone - familiarity with music and TV interviews sets this expectation. Sometimes it is better not to make such a big showy statement. People act differently when they see a microphone, in the same way as taking out a camera can change a scene.

For those situations where it isn't actually necessary to hide the microphone, but it would be nice if it was not so obvious that a recording was being made, in-ear binaural microphones find a niche. Typical users are urban recordists, podcasters and other field recordists in spaces containing people who are part of the action. These spaces typical contain a lot of people using Ipods and mp3 players with earbuds, and nobody will notice yet another person with earbuds which, instead of producing sounds, are recording them.

Core Sound and Sound Professionals in the US and the German company Soundman are among the suppliers of this type of microphone. The recorder needs to be able to supply plug-in-power on a 3.5mm minijack, so they work well with the cheaper end of the recorder market, rather than with professional kit with 48V phantom powered XLR jacks.

Using head-worn binaurals is simplicity itself - go to location, insert earbuds and start recording. However, there are some pitfalls for the unwary. The recorded stereo image will track the wearer's head movement. On playback, it can sound as if the world suddenly spins round in the opposite direction, so the recordist needs to turn their head slowly, or be prepared to edit these sections out. Likewise the stealth concert taper sometimes stands out with their wooden stance while others in the audience respond to the music.

Binaurals are omnidirectional in nature, so there is no opportunity to discriminate against sounds from particular directions, including behind the recordist. Although omnidirectional mics are usually least affected by wind noise, the binaural setup does not really favour using wind protection. There are few things that look quite so ridiculous as a stealth recordist using furry windgags in their ears.

Solve Plug-in-Power Issues with a Battery Box

The use of plug-in-power is convenient, inasmuch as there is no microphone battery to worry about. However, some recorders do not supply sufficient power, which leads to distortion with loud sounds. This is a particular issue for concert tapers who often use them.

A rock concert is very loud, and easily overloads a microphone starved of plug-in power. Using a battery box to power the binaurals from a 9V battery can solve this problem - the signal can then even be taken into the line input of the recorder which does not have plug in power but can handle higher signals without overloading than the mic inputs

Pros and Cons of Head-Worn Binaural Microphones

Using Binaural Head Worn Microphones Not Mounted on the Head

Although binaural microphones are designed to be worn in the recordist's ears and give by far the best binaural stereo effect that way, they can be used wider apart as spaced omnis, or simply laid on a flat surface about a head width apart.

Alternatively, with a piece of string mics can be placed either side of a tree, or a suitable room pillar can be pressed into service as a substitute head. If the tree or the pillar is about 7 inches in diameter, the results are very close to binaural, without the problems of stereo image stability due to head movement.

Binaural microphones are a useful tool for the urban field recordist and podcaster. Users should, of course, respect the copyright in any musical performances and the local laws regarding recording conversations.

The copyright of the article Binaural In-Ear Head Worn Stealth Microphones in Recording Engineering is owned by Richard Mudhar. Permission to republish Binaural In-Ear Head Worn Stealth Microphones in print or online must be granted by the author in writing.