Stereo Mic Tech - Robs exam

ORTF stereo

NOS Stereo

XY

A-B / Baffled Stereo

Decca Tree

Double MS

Two first order cardioid microphones, Spacing of 17 cm between the microphone diaphragms, An 110° angle between the capsules.

ORTF Stereo

17 cm

110 degree

ORTF Stereo

Reproducing stereo cues that are similar to those that are used by the human ear to perceive directional information in the horizontal plane.

The distance between the human ears

The shadow effect of the human head.

XY Stereo

Exhibit proximity effect and will result in low frequency loss., You could add low frequency with an Equalizer to desired taste.

The French Radio Organization

ORTF Stereo

Two first order cardioid microphones spaced 30 cm and angled 90° creating the stereo image.

30 cm, 90 degrees

Loose the low frequencies due to the use of pressure gradient microphones, The Influence of the proximity on these type of microphones.

Shorter distances, For example on piano, small ensembles or used for creating stereo on a instrument section in a classical orchestra.

Dutch Broadcasting (Nederlandsche Omroep Stichting).

NOS Stereo

RAI technique, the cardioid microphones are 21cm apart and at an angle of 100 degrees.

RAI stereo

Olson technique, The cardioid microphones are 20cm apart and at an angle of 135 degrees.

Olson stereo

Two first order cardioid microphones in the same point (coincident) and angled to create the stereo image.

90 degrees

120° to 135° or even up to 180°

Put one microphone on top of the other with the diaphragms vertically aligned.

Difference-in-level-stereo.

Stereo Image

difference-in-time-stereo

High Mono- compatibility is needed, For example, in broadcasting situations where many listeners still receive the audio on mono equipment.

XY Stereo

Close miking application choice.

Spaced microphone stereo techniques using an acoustic absorbent baffle.

Generic term for a lot of different stereo techniques using an acoustic baffle to enhance the channel separation of the stereo signals.

Acoustic absorbent and Non-reflective material to prevent any reflections on the surface of the baffle to cause coloring of the audio.

Two omnidirectional microphones placed in the ears of a dummy head creating the stereo image.

Binaural Stereo

Binaural recordings

Enhance the clues for localization, but those enhancements are usually easier to perceive on headphones than on speakers.

Two bi-directional microphones placed in the same point and angled 90° creating the stereo image.

coincidence stereo technique.

coincidence stereo technique

Shorter distances to the sound source, as bi-directional microphones are using the pressure gradient transducer technology and therefore is under influence of the proximity effect

loose the low frequencies.

Intensity related stereo information.

Blumlein Stereo

One first order cardioid microphone and one bi-directional microphone in the same point and angled 90° creating a stereo image through a so called MS-matrix.

Is a coincidence stereo technique, which uses two bi- directional microphones in the same point and angled at 90° to each other.

MS-matrix

MS-stereo

Mono compatibility.

Two spaced (omnidirectional or cardioid) microphones to record audio signals.

40 and 60 cm

Detectable by the human ear, as this distance is equivalent to the distance between the two ears themselves.

Richer bass response, making the bass loss at distances much less critical., These mics are a good alternative to omnis when a little directionality is preferred or needed. The sound color is very similar to our omnis.

If a desire to include more of the room sound, or to achieve a flattering capture of the instruments, has led to a mic placement that is farther apart.

Two (or three for large ensembles) omni-directional microphones evenly placed in front of an ensemble.

Spaced Omnis

Every 1 unit of distance from the sound to the microphone should be 3 units of distance between microphones., Example: microphones are 5 feet in front of the ensemble - the distance between the two microphones cannot be less than 15 feet - 7.5 feet each from the center line.

Three-point pick-up by 3 omnidirectional microphones in a (often equilateral) triangle pointing at the sound source.

Decca, the "tree"

"hole in the middle"

60cm to 120cm

Slightly lower than and in front of the outside pair.

The tree can be raised or lowered to achieve the best result.

Right behind or Over the conductor which results in a sound balance very close to his intention.

A time coincident, compact and adjustable surround configuration

Using a front- and a backwards pointing MS set, sharing the same Side microphone.

2 different transducer technologies are used for the cardioid Mid mic and the bi- directional Side mic