Stereophonic Microphone Technique
Classic Blumlein Technique
For many years, several “coincident” microphone setups have been widely used for picking up
sounds in stereo as naturally as possible. The “Blumlein” technique, named for A.D. Blumlein of
England, involves the use of two figure-eight microphones positioned as in the sketch
(see
Figure 1)
; so that one faces left and the other, right, at an angle of 90º (i.e. each displaced 45º
from center).
Each microphone ultimately feeds one speaker in a stereo system, and due to the directionality of
the microphones, the result is a very well defined stereo effect on playback. For classical music,
particularly, the reproduction can be very satisfying.
Figure 1
Classic Blumlein or “coincident” miking technique
Mid-Side Technique
In the early days of stereo radio broadcasting, there was need for a mic setup that would allow
for simultaneous stereo and mono feeds from the same mic array. The result was what is now
known as the mid-side microphone technique. One mic faces sideways, one faces forward as
shown in Figure 2, and they are connected as shown in Figure 3. When the outputs of the pair of
microphones are combined at the mixer, they will behave like a pair of microphones, one facing
left and one right, provided that levels are adjusted so the microphone’s outputs are matched. The
width of the stereo image can be widened or narrowed by varying the ratio of the side mic to mid
mic: turning down the side mic all the way will give a mono pickup.
13
L
R
Содержание Active Ribbon SF-2
Страница 18: ...Polar Pattern Frequency Response 18 ...