A polyphonic analog synth introduced by Sequential Circuits in 1983. It was an eight-voice synth based on the voice architecture of the Prophet-5, with many additional control system routing possibilities. Among other things, this accommodated signals from the 76-note (A to C, oddly), piano weighted keyboard equipped with both velocity and polyphonic aftertouch sensing. (Unlike the Prophet-5 and 10, whose keyboards had neither.) The synth also had a built-in sequencer, and all units came equipped from the factory with MIDI.
The T8 was intended to replace the Prophet-5, which Sequential wished to discontinue production of in order to make factory floor space for new models. Unfortunately, due to development problems with the keyboard mechanism, introduction of the model slipped from 1981 to 1983, and when it did finally appear, the list price was considerably higher then the P5. This, along with the misfortune of being introduced shortly after the Yamaha DX7, meant that demand was weak. Only about 350 were sold.
Today, the T8 is quite valuable in the collectors' market. The keyboard is considered one of the best ever put on a synth. In fact, the keyboard made it possible for the T8 to have the last laugh, in a way: New England Digital was so impressed by it, that they purchased T8 keyboard mechanisms from Sequential for use in the Synclavier.