REQ: Fuse Audio Labs VCL-4 Vintage Opto Leveler

The VCL-4 is a faithful emulation of the silver face revision of the op amp based successor of THE classic late 60s opto leveler. It provides you with unintrusive to extreme program dependent and musical opto compression. The switchable ratio option makes for a flexible solution over a wide range of source material.

During the modeling process we rebuilt the entire original circuit on strip board, however replacing the original opto-cells that were made up of an LED and an photoresistor with suitable Vactrols. Every part of the circuit including the receiver stage, the side-chain and Vactrol LED driver circuit, the Vactrol itself as well as the push-pull driver stage and the output transformer has been accurately modeled.