The Yamaha PortaSound PSS-470, a toy keyboard released in 1986 was based on the same Yamaha YM3812 (aka OPL2) FM synthesizer IC used in first generation IBM PC sound cards. It has 9 voice polyphony or 6 voices with 5 drum sounds.
The PSS-470 is more versatile than most toy keyboards in that it has simple manual editing using six sliders for shaping the FM sounds.
- Wave selects the sound colour.
- Spectrum adjusts the pitch of the sound selected by the Wave setting. Reducing this will enable deeper bass sounds.
- Modulation adjusts the sound brightness.
- Attack adjusts the time a note takes to reach its peak volume.
- Decay adjusts the time a note takes to become inaudible.
- Volume controls the output level of the synthesizer section.