The Echo Ohce consists of two independent circuits. The first is an optical compressor based on the DOD 280, combined with a modified clone of the Boss SG-1 Slow Gear. The Slow Gear section has a 3-way toggle switch to change a key capacitor that effects the swell time. Combined with the compressor, this version yields long swells WITH long sustain, even when the toggle is in the "Fast" position. The delay + modulation side is based around the PT2399 delay chip popular among boutique builders. I only had room for 1 chip in this first design, so the max delay time is 580ms. My goal is to add a second chip in the next revision. The enclosure is hand-painted, and I will build only 17 of these.