ADDAC SystemADDAC803 Quadraphonic Spatializer

ADDAC System ADDAC803

The ADDAC803 Quadraphonic Spatializer is a multi-channel panning module that uses the VBAP (vector base amplitude panning) principal to pan mono signals in quadraphonic space. There are two modes, Cartesian and polar, each providing its own means of orienting a sound in space.

In Cartesian mode, the module defines the position based on an X/Y axis. X moves the sound left to right and Y moves the sound forwards and backwards. In polar mode, the sound moves in circles. Radius sets the distance away from the center, angle moves the sound in a 360 degree field. With radius set to zero, angle does nothing; as the radius is increased, the signal diverges farther from the center of the space. Controlling angle with linear ramps can produce continuous circular movement; using more novel modulation shapes creates more interesting spatial trajectories.

When a modulation signal is plugged into the corresponding CV input, the knobs act as CV attenuators. X/Y CV outputs put out a voltage that follows the X and Y position in Cartesian mode. Each of the four channels has a CV output that mirrors the panning behavior and is indicated by LEDs. The filter +/- outputs provide voltages that change relative to the distance to the spatialization edges and reacts to the filter curve knob. These can be used to create naturalistic filtering effects, for example, by modulating a lowpass filter cutoff as a sound moves from a center position, eliminating higher frequencies as the sound moves from the center. Spatialization curve sets the amount of spatialization and offset manually sets the offset for the angle parameter. The four output channels are produced both on Eurorack standard and line-level quarter inch instrument jacks.

ADDAC803 Features

• Quadraphonic panning module
• Two modes for panning: Cartesian and polar
• CV output per panning channel
• Outputs on both 3.5mm and quarter inch jacks
• X and Y CV outputs based on position and CV inputs in Cartesian mode
• Filter CV outputs follow the position from the center point
• Unipolar or bipolar CV inputs with switches