and can modulate each other using PM or ring modulation (the latter not available in Yamaha's system). Casio's options for combining and routing oscillators are more flexible than Yamaha's. For example the VZ10-M is capable of 90 unique combinations of oscillators and modulations compared to the 32 algorithms of the DX7. Additionally the VZ-10M oscillators offer 8 different waveforms, allowing more complex sound generation than the DX7 which uses only sine waves. External links US4658691 - Electronic musical instrument (Masanori Ishibashi, Casio Computer Co Ltd, Priority Oct 17, 1982) US4479411 - Tone signal generating apparatus of electronic musical instruments (Masanori Ishibashi, Casio Computer Co Ltd, Priority December 22, 1981) Virtual Phase Distortion Synth pdhalf − The Canonical Csound Reference Manual. «The pdhalf opcode is designed to emulate the "classic" phase distortion synthesis method of the Casio CZ-series of synthesizers from the mid-1980s.» Sound synthesis types Japanese inventions