Twelve fun ways to use miniature mics

One mic

BLM recording

If you make a recording in a room, in a car cabin, or the like, it is often advantageous to use a boundary layer microphone (BLM). However, the boundary layer technique is not restricted to be used with dedicated BLM-microphones. A miniature microphone and a piece of tape can do the same job! Tape the microphone to the dashboard or ceiling of a car, the tabletop, the wall, the ceiling or the window. You need a reflective, predominantly flat surface (as big as possible) to support the sound. The advantage is the lack of reflections that may color the sound. Further the SPL of direct sound is doubled (+6 dB) in the reflective surface, whereas diffuse sound is only gained by 3 dB; directionality - in all directions!

Recording musical instruments

When you amplify or record musical instruments, you often need to get close to the source. The miniature microphone can be mounted on the instrument, allowing you to get close to the specific sound without adding additional weight and allowing you to play the instrument unaffected by the installation. For instance, inside an upright bass; it gives a fantastic sound and very good isolation. Also, remember to select a microphone that can handle the instrument's SPL without being noisy due to a limited dynamic range.

Sound effects

One advantage of miniature microphones is that you can put them anywhere. If you are recording sounds for sound effects or sampling sounds for music and other compositions, you can acquire sounds no one else usually hears – inside an old clock, an anthill, a tube (resonant recording), the possibilities are endless. Remember to check that the microphone can handle dust, humidity and other environmental challenges.

DYI hydrophone for underwater recordings

A hydrophone is a transducer that records underwater sound. Take a whisk (not too big – one from a hand mixer is excellent) and place the miniature microphone in the middle of the “cavity”. Keep the mic in position by using rubber bands or tape. Add some heavy weight to the bottom of the construction (to make it go down in the water)and a tight, flexible cover around the whisker (condom or balloon). Ensure it is watertight by using rubber bands or something similar. Also, if you need a cable extension, ensure this is watertight

Make a BIG microphone

If you have a large, old microphone that no longer works, try installing a miniature microphone inside the grid and let your friends try your big microphone. Most people are fooled into believing this big microphone is fantastic! 

Two mics

If your microphones do not have identical sensitivity, i.e., because of tolerances or using different models, you can calibrate them. This is done by keeping the microphones close together and playing some noise (i.e. pink noise) through a small loudspeaker (even a smartphone may work). Place the microphones at some distance (30-50 cm) and adjust the gain of each microphone to reach the same level in your recording.

Percussion sleeve recording

How many mics would you use to mic up the kitchen? Percussionists usually have lots of instruments to hit, so it may take several microphones. However, a more fun solution is to mount a miniature microphone on each of the drummer’s wrists. Then, the mics follow the hands, so to speak.

Stereo glasses

If you want to make a “secret” recording, attach a miniature microphone to each spectacle rod on a pair of glasses. This recording form is not precisely binaural; however, it is okay to playback using headphones or a basic LR-loudspeaker setup.

Binaural recording

If you need a binaural headset, you can “fake it” by attaching a miniature microphone to each ear (on pinna). Make sure it does not rub against your ear flap or hair. Playback and listen via headphones. If you need wind protection, wear a beanie covering the ears.

Creating a figure-of-8 from two omnis

Sometimes, it is fun to experiment with extreme directionality of microphones. For instance, you can create figure-of-eight characteristics by connecting two miniature omni microphones to one input! All it takes is that the microphones have a balanced output – which they don’t… However, if you use an XLR-adaptor (for DPA miniatures,  DAD 6001), you can apply two identical miniature mics and a phase inverter (swapping pin 2 and pin 3 of the XLR) on one of them. Add the two signals using a passive summing device. Or if you have the luxury of possessing a small sound mixer, use two channels, both panned to the center (or the same side). If this mixer has an inverter on the inputs, use it on one of the channels (to avoid the cable inverter). Experiment with the distance between the mics and/or add a disc between the mics. Now you just made yourself a pressure gradient microphone!

More mics

Immersive recording with a drying stand  

A professional mike-stand for immersive recordings seldom comes cheap. However, you can have a collapsable solution using a drying stand and miniature microphones. You can even obtain a variable basis distance between the mics. If you make a recording with height information, the upper layer of four mics can be mounted at the end of each rod. The main layer can be the microphones suspended by their wire, approximately 1 meter below the upper mics. Tie in a knot just above the mic to force it down (if the cable is a little curly).

Multichannel BLM

Instead of using a stand for your multichannel recording, you can put the mics on the ground. For instance, you could arrange the microphones in a circle. If you are outdoors, the wind is much lower near the ground than in the air. Indoor, it is excellent for recording in reverberant spaces.

Dynamic multichannel recording

This is a method for recording artistic performances involving a group of people (sound art or theatrical use). Each person has a microphone mounted on the head (cap, beanie). They each carry a sound recorder or wireless transmitter. All channels are recorded and eventually synchronized. In principle, all the people can be in very different places and move to one place, perhaps followed by yet another repositioning. In a theatrical multichannel reproduction, you will experience a very diffuse world that suddenly concentrates and maybe dissolves again.