Decca tree

The Decca Tree layout had no fixed measures.

The Decca Tree is a spaced microphone array most commonly used for orchestral recording.

It was originally developed as a sort of stereo A–B recording method adding a center fill. It is the most commonly used spaced-pair technique. The technique was developed in the early 1950s and first commercially used in 1954 by Arthur Haddy, Roy Wallace, Kenneth Wilkinson, Stan Goodall, and their team at Decca Records, to provide a strong stereo image.

Setup

A Decca Tree setup includes 3 omnidirectional microphones in an upside down "T" pattern. The left and a right mics are placed about 6 feet apart, and the third is placed 3 feet out and centered in front. To mix, the side mics are panned hard left and right, and the output of the middle mic is then sent to both left and right channels.

The Decca Tree was originally used in orchestral situations, fitted on a tall boom and suspended high up in the air, roughly above the conductor. Three separate stands were sometimes used to set individual heights.

Microphones

The technique traditionally uses three omnidirectional microphones, traditionally of the Neumann M-50 small-diaphragm pressure transducer tube condenser type, to record in stereo. These microphones are not truly omnidirectional at the higher frequences, but exhibit some high frequency lift and directionality which is likely to positively affect stereo imaging of the Decca Tree arrangement. Variations have been performed using a coincident pair, in X-Y, Mid/Side (M/S), or Blumlein positioning, in place of the center microphone. The Schoeps M 201 and Neumann KM 56 were also used by the Decca team.

Applications

The Decca Tree is a great sounding stereo miking technique often used in large orchestral or choir performances, but it can also be used as a room miking technique for recordings. When used for room miking drums, its wide stereo image captures the nuances of bigger environments better than most other techniques. In smaller rooms however, the Decca Tree does not work as well.

Ron Streicher, author of "The Decca Tree — It's not just for stereo any more" has also described methods for employing a Decca Tree for surround recording. He utilizes a SoundField MK-V for the center, a pair of Schoeps MK21 sub-cardioid condensers for the left and right, and a pair of Schoeps MK41 hypercardioid condensers for the left and right surrounds. The MK-V affords a number of possibilities to the Decca Tree, as it is a four-element transducer that can be decoded into 5.1 and 7.1 sound fields on its own, using the SoundField SP451.

External links

• Decca Tree Recording with Georg Neumann pressure microphones M 50 - in German — pdf
• Pictures of Decca Tree used in a session at Abbey Road Studios
• The Decca Tree — A classic microphone placement system of the 1950s
• The Decca Tree — It's not just for stereo any more — pdf
• A Decca Tree primer — Wes Dooley, Audio Engineering Associates AEA — pdf
• Stereo Bars and Decca Trees — Wes Dooley, Audio Engineering Associates AEA — pdf
• WikiRecording's Guide to Decca Tree Use and Setup

References

• Huber, David Miles; Robert E. Runstein (2005) Modern Recording Techniques (Sixth ed.) Elsevier, Inc. ISBN 978-0-240-80625-9