Microphone Techniques

I.  Coincident:  Microphone diaphragms are located within the same vertical plane.  Sound waves reach both capsules at the same time, so direction cues are limited to intensity.

Blumlein (Blumlein Crossed Figure-Eights Technique):  Two bidirectional (figure-8,bi-polar) microphones crossed at 90 degrees, aimed toward 45 degrees left and right of the sound source.   3dB decrease? in sensitivity at the overlap in the center.

• 2 figure-8 (bi-polar)

X-Y: Two cardioid mics placed facing each other at 90 degrees.  The center of the sound source situated at the apex of this angle. 

• 2 cardioids

• 90 degrees; 110 degrees (hyper-cardioids)

M-S (middle-side):  Stereo mic placement technique.   Cardiod mic is placed toward the sound source (M, Mid, Middle, Mono).   Figure-8 mic is positioned so that the two lobes of this pattern are directed towared the sides (S,Side,Stereo).  

• 1 cardioid toward source

• 1 figure-8 placed sideways

II.  Near-Coincident:  Microphones positioned within the same horizontal plane.  Timing difference cues

ORTF ( Office de Radiodiffusion Television Francaise):  Developed by the French national broadcasting system.  

• 2 cardiods 

• 17 cm apart

• 110 degrees

• Overall coverage = 180 degrees

NOS:  Dutch Broadcasting System. 

• 2 cardiods

• 90 degrees

• 30 cm

• Overall coverage = 160 degrees

III.  Spaced Micing Techniques:  Two or more microphones spaced several feet apart.

A-B Technique:  Spaced technique utilizing omni-directional microphones.  Creates a center phantom image.  Good presence and ambient space reproduction.  Often used to record large ensembles particularly in jazz and classical music.  Poor mono compatibility?

• spaced omni-directional mics

Decca Tree: fgff

Binaural (Kunstkopfstereophonie):  Published on Funkausstellung (Berlin) 1973.  An attempt to more accurately represent the way in which humans hear sound based on the shape of the head.

Boundary Mics:

Dynamic

Condensor

Electret

Moving-Coil

David Thoener's Typical Mic Setup
Kick: D112 outside, 47 FET inside
Outside, build a tunnel with mic stands and blanets to keep cymbal leakate to a minimum.
Snare:  SM57 top and bottom, bottom mic gated so I don't get the kick rattling the snares.
Toms:  MD421s.  Sometimes I might throw a mic on  the bottom head of the lowest tom for low lows.
Hi-hat:  KM84.
cymbals:  421.
Room: C012s
Percussion:  57s and 451s, sometimes an overhead 87
Bass: Demeter DI, and on the bass a mp an RE-20. Also on bass:  dbx 160s with light compression, 1dB or so at 2 to 1.