The instrument
The TG 55 is a 16-voice polyphonic and 8-voice multitimbral synthesiser module with 4 PCM oscillators. It is comparable to the SY-55 keyboard, which was released a year later. The synthesiser is based on the SY 77 keyboard, which was released at the same time, and has an almost identical version of its AWM2 section, Yamaha's second generation 16-bit Advanced Wave Memory, a digital system for storing and reproducing waveforms, and the effects section. In contrast to the SY series, it lacks the sequencer.
Details
The sound generation of the TG 55 is based on the AWM2. It has 74 waveforms in the 2 MB sample ROM and additional cards, 16 multis, two programmable drum sets and an effects processor with 34 effect types. It has card slots for DATA and WAVE. The TG 55 has two operating modes: Voice and Multi. In Multi mode, the voices are dynamically assigned to one of the 16 MIDI channels. A voice consists of one, two or four elements, each of which is linked to one of the 74 waveforms. A voice with one element has full polyphony with 16 notes, a voice with two elements with 8 notes and a voice with four elements with four notes. The waveforms are sampled at 32 or 48 kHz, processed internally at 24 bits and converted via 22-bit digital-to-analogue converter.