Casio CZ-1000 review

(I originally posted this at Gearspace)

In the 1980s, digital technology made programmable polyphonic synthesizers affordable. While other companies made low cost (or, should I say, lower cost) digital or hybrid synths first (Korg led the way in the early 1980s, with their Polysix, Poly-61, and 707 synthesizers), Casio made fully programmable polyphonic synthesizers really affordable with their CZ lineup.

With a street price in 1986 of only $300, the CZ-1000 made it possible for pretty much anyone to get a synthesizer. It was no preset synth: The machine was fully programmable.

The CZ series uses a very crude simulation of analog synthesizers called “Phase distortion”. A sine wave is modulated to sound like a sawtooth, square, pulse, or any of a few non-traditional waveforms — a waveform “morphs” between a sine wave and the waveform with full harmonics, sounding something like a classic analog filter.

Since the synthesizer is fully digital, it is more flexible than a traditional analog synths in a few ways: I already mentioned it had more waveforms than an old-school analog synth; it also uses eight stage envelopes instead of a traditional ADSR envelope. When two oscillators are stacked, each oscillator can have its own pitch, filter, and volume envelope.

Since the phase distortion filter did not have filter resonance, three of the eight waveforms included with the CZ series crudely emulated it.

In addition to a simple pitch vibrato, the CZ synthesizer allows the two waveforms to be ring modulated, allowing a lot of “DX7” style sounds, as well as having the second oscillator “noise” modulated, which can make for some interesting percussive sounds.

The CZ synths, when emulating a classic analog synth, tend to sound somewhat thin. Some of the CZ’s non-analog waveforms, when combined, sound less thin, albeit with a distinct digital quality to them. I got my best results for pad sounds from the CZs using external processing; it can have a great electronic analog sound by being run through a guitar phaser pedal.

It is possible to stack up to four oscillators on a single sound via “tone mix”, which is especially useful for synth bass sounds. The CZs are good at making deep bass sounds.

It’s very flexible; I spent years before I had money to buy other synths exploring all of the sounds this thing can generate and finding some pretty amazing sounds in it years after a bought it, including a voice-like sound (generated with ring modulation) my friends thought was a digital sample.

Once advantage of using mostly digital parts is that these critters tend to hold up well. However, after two decades, the relays in my CZ-1000 started acting up and the line out sometimes does not work. The headphone output still works, and while most shops will not repair a CZ-1000, the replays can either be replaced, or more simply cleaned.

These had a street price of around $100 in the mid-2010s; these days, COVID-19 has increased the price of synthesizers so these start around $250 ($150 if in “for parts” condition).