Blumlein technique

The Blumlein technique is a system of placing microphones to achieve stereo sound recording, included within the so-called coincident pair techniques. It is also known as stereophonic technique, as it is the most used.

It was developed by the British engineer Alan Blumlein (1903-1942) in the 1930s.

Layout

Two bidirectional microphones are placed at a 90° angle, so that the diaphragms of both microphones coincide on an imaginary axis.

It is the most used technique due to the multiple advantages it offers:

1. Deliver a uniform reverberation.
2. It provides a defined image. Defined location and excellent sense of depth.

The main drawback of Blumlein's technique is that it only works well in a large room and when no strong signals are present on either side of the stereo pair.