Stereo Microphone Techniques
One of the most popular specialized microphone techniques is the stereo microphone technique. Discover how this method enhances sound capture and creates immersive audio experiences.
Benefits of Stereo
Using stereo miking can significantly enrich your mix, providing a high-quality sound that draws listeners in. There are no strict rules or limitations; the beauty of this technique lies in your imagination and willingness to experiment.
Beware of phase cancellation, where out-of-phase signals reduce or cancel each other. Fully out-of-phase signals cancel completely, while slight offsets cause a "warble" effect. Panning can reduce the issue, but always check in mono for clarity and balance.
Four Main Types
There are four main procedures for stereo miking, including:
Spaced Paired
Microphone Type: 2x cardioid or omni-directional
The space paired technique is the easiest of all the stereo microphone techniques and is simply two microphones placed in front of an instrument, with one being placed to the left and the other to the right.
The distance between the two microphones can vary between 10 centimeters to 10 meters. The exact distance is usually determined by the size of the instrument, the size of the room and how many instruments are being recorded.
The spaced pair technique can obtain a large stereo image providing a bright open sound.
There is a drawback to the spaced paired technique. Often there is potential for phase cancellation and comb filtering due to the difference in the arrival of the sound to the two microphones. To help eliminate the problem of phasing, keep both microphones at exactly the same height and distance from the instrument. A mono reference source can be used to check for phase problems.
The spaced pair technique can be used with omni, but mainly uni-directional microphones.
X-Y (coincident)
Microphone Type: 2x cardioid
The X-Y technique involves a pair of cardioid microphones of the same make and manufacture placed with their heads facing as close together as possible at an angle of around 90-110 degrees.
The midpoints of the two microphones should be pointing towards the source, with the outputs being equally panned left and right. The two microphones should be placed within close proximity to the sound source.
The X-Y technique produces a relatively narrow stereo spread but good imaging. Due to the microphones' close proximity, there are no phase problems that can be seen with the spaced pair technique above.
Mid-Side
Microphone Type: 1x cardioid, 1x bi-directional
The mid-side configuration combines two types of microphone, one being either a cardioid or omni directional microphone (the mid), and the other being with a figure-eight microphone (the side). The cardioid/omni microphone is placed in the middle facing straight forward, while the figure-eight microphone is placed facing ninety degrees to the side.
The mid-side technique provides good stereo spread, stereo imaging, and localization. The configuration can usually be placed on a single microphone stand.