The Blumlein Pair is a stereo recording technique invented by Alan Blumlein for the creation of recordings that — upon replaying through headphones or loudspeakers — recreate the spatial characteristics of the recorded signal. Symbol for stereo Stereophonic sound, commonly called stereo, is the reproduction of sound, using two independent audio channels, through a pair of widely separated speaker systems, in such a way as to create a pleasant and natural impression of sound heard from various directions as in natural hearing. ... Alan Dower Blumlein was an electronics engineer who made a great many inventions in telecommunications, sound recording, stereo, television and radar. ...

The pair consists of an array of two microphones of bi-directional (figure 8) pattern turned 90° from one another. Ideally the microphones would occupy the same physical space; as this is impossible the microphones are placed as close as physically possible. The array is oriented so that the a line bisecting the angle between the two microphones points towards the sound source to be recorded (see diagram). A microphone, sometimes called a mic (pronounced mike), is a transducer that converts sound into an electrical signal. ...

The Blumlein pair produces an exceptionally realistic stereo image, but the quality of recordings is highly dependent on the acoustics of the room.

The traditional microphone for Blumlein Pair recording is the ribbon microphone, although some microphones are purpose-built for the type of coincident arrangements that are required for the Blumlein pair, for example the Studio Projects LSD2. A Ribbon microphone is a type of dynamic microphone that uses a thin metal ribbon placed between the poles of a magnet. ...

Bidirectional (Figure 8) Microphone Sensitivity Pattern (Red dot is microphone, viewed from above)	Blumlein Pair Array (2 crossed Figure-8s) (Small arrows indicate front of individual microphones, large arrow indicates front of array.)