The Trident is a polyphonic and programmable instrument with three independent sections - Synthesizer, Brass, and Strings, released in 1980. It features 8 voices of polyphony and two of the instrument sections can be played simultaneously while in Split Keyboard mode.
Each section has its own unique VCO voice architecture, VCF (filter) types, and LFO capabilities. The Brass section's VCF and Envelope Generators are virtually the same as the Synthesizer section, allowing the Brass section to be used for generating additional synthy sounds as well as faux-brass sounds. The String section has some unique features as well such as a "Bowing" effect. Another unique effect included is a global flanger that can self-oscillate! Flanger controls include Speed, Feedback, Intensity and Manual.
The Trident featured 16 user memory patches. In addition there were three preset memory patches for Piano 1, Piano 2 and Clavi. There is no way of externally playing the Trident with MIDI or CV/Gate without modifications (CV/Gate only controls expression and filter parameters). But the CV/Gate inputs are discrete for each of the three sections. There are also discrete mono outputs for each section and a mix output.
The Trident mkII version released in 1982 had doubled the memory (32 patches), an independent envelope generator for the VCF (filter) section and more. The specifications listed are for the mkII since it is the more popular and common of the two. The Tridents sound very nice, warm and analog and have been used by Rick Wakeman, Joe Zawinul and Phoenix.