A manufacturer of various synth accessories based in the USA (and not to be confused with another company of the same name, which makes network routing equipment). Encore has three main lines of business. The first is retrofit and expansion products for mainly out-of-production synths, including MIDI retrofits for some late-1970s and early-1980s polyphonic synths, and DSP expansions for some 1990s model synths. The second line of products consists of MIDI interfaces, including the well-known Expressionist MIDI/CV converter. The third line consists of a few specialized modules for modular synths in various formats, including a universal event generator and a frequency shifter with an innovative circuit design.
Encore Electronics web site (Note that there is another, unrelated Encore Electronics that makes network equipment, so use this link)