atk-sc3/Classes (extension)
| Libraries > Ambisonic Toolkit > UGens > FOA > Transformer | UGens > Multichannel > Ambisonics
FoaDirect
Extension
ExtensionFirst Order Ambisonic (FOA) directivity transformer
Description
Adjust the soundfield directivity of a First Order Ambisonic signal (B-format) across an arbitrary plane.
Class Methods
.ar
Arguments:
| in |
The B-format signal, an array: [w, x, y, z] |
| angle |
The distortion angle, in radians. 0 to pi/2 |
| theta |
Azimuth for the normal to the plane, in radians. |
| phi |
Elevation for the normal to the plane, in radians. |
| mul |
Output will be multiplied by this value. |
| add |
This value will be added to the output. |
Discussion:
Angle = 0 retains the current directivity of the soundfield. Increasing angle towards pi/2 decreases the directivity along the normal defined by theta and phi, reducing the gain on this normal to zero, and is equivalent to a spatial low-pass filter. The resulting image becomes directionless on the normal.
NOTE: Corresponding matrix transformer: FoaXformerMatrix: *newDirect