About
CASIO VZ-1 is the first iPD (Interactive Phase Distortion) synthesizer.
CASIO VZ-1 (1988)
A single voice is made with 8 oscillators, freely patched like a modular synthesizer, using Mix, Ring Modulation, Phase Distortion.
About the iPD sound:
CASIO made a demo tape when releasing VZ-1. It begins with the narration - "Get ready for a whole new experience in sound - the all new CASIO VZ-1 digital synthesizer." Indeed, the presets are well programmed and very impressive.
VZ's phase distortion tends to generate pulsy, square-wave-like odd harmonics. I guess that's why VZ uses saw waves as the preset waveforms. Analog filter emulation is not easy with VZ - it's more easy to create digital noises and plucked sounds, as in the impressive preset called 'Gitiano.'
PD between 2 sine waves sounds like square wave generated by 2-OP FM synth. Putting more oscillators in PD, more metallic, noisy harmonics are generated. Detune and fixed frequency are useful for complex sounds.
Here are some .mp3 examples of the single sounds of VZ-8M - 1U rackmount version.
No external effects, no overdub used.
See also Roland GP-8 multi-FX page for the effected sounds of VZ.
Sine EP (282KB)
VZ-1 is the first iPD model, and it's a good master keyboard. Its large blue LCD display with envelop graphics was much ahead of that time. It has a pitch bender and two wheels - called Definable Wheels - later copied by YAMAHA SY77 / SY99.
VZ-10M is the 2U rackmount, and VZ-8M is the 1U rack. VZ-1 and VZ-10M are 16 polyphonic, and VZ-8M is 8 polyphonic. I sometimes experienced a little MIDI delay with VZ-10M - its 128 oscillators may have burdened much the late-80s processor.
The VZ series and the FZ-10M sampler share the 'CASIO professional' logo.
Guitar synthesizer CASIO PG-380 etc. used VZ's iPD engine, and can use the same RAM card with VZ.
VZ-10M (1988)
VZ-8M (1989)
CASIO CZ series are the early generation of PD synth. As it uses more suitable Phase Distortion waveforms and other tricks like resonance emulation, it's very good at emulating analog synthesizer.
In a sense, VZ's architecture is more simplified than CZ, except the number of oscillators, as VZ basically works with PD/Ring/Mix only. I wish CASIO simply updated this CZ series with the iPD - retaining the analog-emulating techniques while adding interactive Phase Distortion between the oscillators. It could have been a very powerful, yet easily editable, near-VA synthesizer.
CASIO CTK-1000 may be related as it's the later version of CASIO's 'nonlinear' synthesis engine, combined with PCM. It's detail is not known, and it's only partially editable. It may also be related to the rare digital synthesizer Evolution EVS-1, which uses PD, FM, Ring Mod, Width Mod, Waveshaping, to connect 4 DCOs with single cycle PCM waveforms.
CASIO CZ-1 (1986)
CASIO CTK-1000 (1993)
The idea of freely patchable inter-modulating oscillators certainly related to YAMAHA DX7 and other FM synths. DX7 has 6 sine wave oscillators, while VZ has 8 with different saw waves and noises. Later, YAMAHA FS1r - the far descendant of DX - acquired 8+8 oscillators with skirt-modulatable saw waves.
YAMAHA DX7 (1983)
Deep Synthesis: Home1. 9. 2007