Electro Harmonix EHX Superego Synth Engine. The polyphonic SUPEREGO Synth Engine reinvents sample and hold, performs fluid glissandos and creates oscillator like, synthesizer effects. It can stack sounds or create infinite sustain, it even lets you tweak attack and decay, or use its effects loop to invent novel synth patches. Moving on as no longer needed.The item "Electro Harmonix EHX Superego Synth Engine" is in sale since Sunday, July 21, 2019. This item is in the category "Musical Instruments\Guitars & Basses\Parts & Accessories\Effects Pedals\Other Guitar Effects Pedals". The seller is "skb558" and is located in York. This item can be shipped to United Kingdom.