The SUS-3 is specifically designed for fixed-biased amplifiers fitted with Power Scaling.

SUS-3 takes advantage of unique connection possibilities provided by the Power Scale circuitry itself. A non-critical 16mm pot provides continuously variable compression for any signal level. The compression will maintain its proportion as the Power Scale control is manipulated.

Adition of RBX will assure proper functioning of SUS-3 to full power. Where the bias supply might have been "adequate" to achieve Power Scale functioning, SUS-3 requires that the raw bias supply be a bit higher voltage.

PCB included, as well as notes including installation tips + layout and schematic diagrams of the kit.

For more info, see "About Our Sag & Sustain Kits".