Output Autogain Quad

s3g Output Autogain Quad folds a multichannel REAPER track down to a four-channel quad output. Use it to audition ordinary multichannel material on a quad system without configuring a complete speaker-layout chain.

The plugin accepts up to 128 input channels and writes outputs 1-4 as L, R, RB, LB. It shares the same layout, rotation, width, 3D weighting, and autogain ideas as Output Autogain Stereo, adapted to a quad field.

Output Autogain Quad layout field, four-output placement, weighting, autogain, and output meters — Output Autogain Quad with layout field, four-output placement, weighting, autogain, and active output meters.

Workflow

Insert Output Autogain Quad on the wide source track, then set the REAPER pins and IN count to include the intended channels.
Route outputs 1-4 to the quad main speakers as L, R, RB, and LB, then begin playback.
Choose a layout model and set width, rotation, weighting, distance, and attenuation for the source geometry.
Select an autogain mode, then adjust OUT while watching all four output meters.
Confirm that unmapped higher track channels are silent and the four destinations receive the intended order.

Output Order

The quad bus is intentionally ordered for straightforward REAPER routing:

Plugin output	Speaker
1	Left
2	Right
3	Right Back
4	Left Back

Controls

Control	Meaning
IN	How many plugin input channels are included in the fold-down.
WDTH	Quad field width. Low values collapse inward; high values exaggerate the field.
ROT	Rotates ring and 3D layouts before they are folded to quad.
AGN	Dropdown menu for autogain: Off, Power/sqrt(N), or Energy sum.
OUT	Final quad output gain trim.
LAY	Dropdown menu for the layout model.
WGT	Controls how strongly the layout shape affects channel placement.
ATT	3D attenuation for layouts with height and rear relationships.
DST	3D distance spread for sphere, hemisphere, and cube layouts.

Layout Models

LAY uses the same layout names as the stereo fold-down: Ring projection, Linear left-right, Odd/even stereo, Center-out, Pair-preserving, Sphere projection, Hemisphere projection, and Cube projection. In the quad version, the channel positions are projected toward four speakers instead of a stereo pair.

AGN and LAY are discrete controls, so the GUI presents them as dropdown menus instead of continuous sliders.

REAPER Pins

The plugin has a four-channel output bus. For a clean fold-down insert, set the REAPER track channel count high enough for the source material, then route outputs 1-4 to the intended quad destination. If downstream channels still show unrelated audio, use REAPER's plugin pin connector to zero unmapped output channels.