1. Recording for Surround Sound

2. What is the end goal?
- stereophonic: concerned only with horizontal reproduction
5.1, 7.1, 10.2, most cinema sound
- immersive: concerned with complete reproduction of soundfield (including height)
Binaural, VR, gaming, 360-camera, Ambisonic

3. Recording philosophy? “Minimalist”
- seeks to capture source and soundfield with a single recording array or microphone
- generally based on stereophonic technique
“Mains + ambience”
- main stereo array for source; separate technique to capture ambience in surround
“Multi-mic + ambience”
- multi-track capture of source + surround ambience

4. “Minimalist” techniques
Same categories as stereo techniques:
- coincident: double Mid/Side, Ambisonic
- near coincident: Williams Arrays, INA5, & others
- spaced: Decca-tree variants: Fukada tree & others
Other:
- Holophone
- Binaural

5. Williams MMAD

6. OCT Uses a near coincident trio of mic's for the front
Recommends separate rear ambience array

7. Double MS
Cardiods facing forward and back, sharing a bidirectional side. Decoded for 4 or 5 speakers

8. Holophone
Proprietary egg-shaped surround microphones

9. Ambisonics
In theory: 4 coincident microphones: an omni (W), and three bidirectionals
X: side, Y: front to back, Z: vertical
Allows mid/side pairs in any direction
Mono, stereo, and surround compatible
Can be rotated, “zoomed”, and flipped
Reality: uses a tetrahedral array of 4 cardioid capsules

10. Binaural

11. Surround ambience arrays
Sources can be captured in multitrack and special arrays can capture the ambience for surround mixing.

12. IRT Cross
Four cardioids at 90 degrees

13. Hamasaki Square
Four bidirectionals, 6 feet apart, aimed 90 degrees off-axis to source for maximum rejection of direct sound