套件： pd-vbap (1.1-2)

Pd library for Vector Base Amplitude Panning spatialization

This a library for Pure Data that provides objects for realtime Vector Base Amplitude Panning. Vector Base Amplitude Panning (VBAP) is a method for positioning virtual sources to arbitrary directions using a setup of multiple loudspeakers. In VBAP the number of loudspeakers can be arbitrary, and they can be positioned in an arbitrary 2-D or 3-D setups. VBAP produces virtual sources that are as sharp as is possible with current loudspeaker configuration and amplitude panning methods, since it uses at one time the minimum number of loudspeakers needed, one, two, or three.

With 2-D setups VBAP is a reformulation of the existing pair-wise panning method. Different from other panning algorithms, VBAP can be generalized for 3-D loudspeaker setups as a triplet-wise panning method. A sound signal is then applied to one, two, or three loudspeakers simultaneously. VBAP has certain advantages compared to earlier virtual source positioning methods in arbitrary layouts. Previous methods either used all loudspeakers to produce virtual sources, which results in some artefacts, or they used loudspeaker triplets with a non-generalizable 2-D user interface.

The directional qualities of virtual sources generated with VBAP can be stated as follows. Directional coordinates used for this purpose are the angle between a position vector and the median plane (θcc), and the angle between a projection of a position vector to the median plane and frontal direction (Φcc). The perceived θcc direction of a virtual source coincides well with the VBAP panning direction when a loudspeaker set is near the median plane. When the loudspeaker set is moved towards a side of a listener, the perceived θcc direction is biased towards the median plane. The perceived Φcc direction of an amplitude-panned virtual source is individual and cannot be predicted with any panning law.