Ambisonics

Reproduction

• Revised versions of BLaH papers:
  • BLaH1: Localization in Horizontal-Only Ambisonic Systems (AES121, 10/2006)
  • BLaH2: Ambisonic Localization - Part 2 (ICSV14, 7/2007)
  • BLaH3: Is My Decoder Ambisonic? (AES125, 10/2008)
  • BLaH4: Design of Ambisonic Decoders for Irregular Arrays of Loudspeakers by Non-Linear Optimization (AES129, 11/2010)
  • BLaH5: Why Ambisonics Does Work (AES129, 11/2010)
  • BLaH6: A Toolkit for the Design of Ambisonic Decoders (LAC2012, 4/2012)
• BLaH Trilogy at Scribd.com [scribd broken, 6/2012]
• Revised version of Benjamin, Lee, and Heller, "Localization in Horizontal-Only Ambisonic Systems"
• Octave/Matlab code from Appendix 1
• Examples for above (sample run)
• Expanded version of speaker_matrix.m (sample run)
• calculates full sets of coefficients (W,X,Y,Z gains) normalized to match pressure and velocities .
• calculates virtual mic patterns
• tabulates r_V and r_E
• Computing shelf filter gains using GNU Maxima.
• Diametric Decoder Patent Documents: GB2073556 US4414430
• Lee and Heller, "Ambisonic Localization -- Part 2"
• Slides from talk at AES 125, "Is My Decoder Ambisonic?"
• Michael Gerzon, "Surround-Sound Psychoacoustics." Wireless World, 12/74
• Integrex Decoder docs and schematics
• Martin Leese's site for Mimim Decoders"

Capture

• Ken Farrar, "Soundfield Microphone." Wireless World, 10/79 and 11/79.
• Calrec Soundfield MkIV
  • User Manual
  • Tech Manual
  • Schematics: 1 2 3 4 5
  • Photo showing capsule backplate
• Soundfield Research ST350
  • Capsule and electronics photos

Test Files

• Eight Directions:
  • B-format AMB (6.8MB)
  • Square Decode DTS/WAV (3.1MB)
  • 2-channel UHJ (3.4MB) Encoded with uhj_encode.m (for completeness uhj_decode.m)
• Pink Noise Pans:
  • Horizontal (x-y plane)
  • Vertical front/back (x-z plane)
  • Vertical left/right (y-z plane)