Contents
- Introduction
- Eight CZ Models
- Phase Distortion (PD) synthesis
- Models in Depth
- Reception
- Notable Musicians Using CZ instruments
- Posters & Ads
- Where to Buy Casio CZ Models
- Where to Repair Casio CZ Models
Introduction
The mid-80s was an exciting time for electronic music and instruments. The first incarnation of the MIDI specification had been finalised, the Atari ST had launched with dedicated MIDI on board, and synth manufacturers were pushing out more powerful instruments at lower prices.
Over three years, from 1984 to 1986, Casio launched its CZ range of low-cost but feature-laden synths. An interesting mix:
- mini and full-size keyed models
- MIDI on all models
- some with an onboard sequencer
- some with speakers and some without
- some with pedal support and others not
- some with tape interfaces for saving data
- some used the MIDI SysEx protocol for sending data to other instruments or a computer.
Eight CZ Models
The eight Casio CZ models are as follows:
- CZ-101 (1984)
- CZ-1000 (1984)
- CZ-5000 (1985)
- CZ-1 (1986)
- CZ-230S (1986)
- CZ-3000 (1986)
- CZ-2000S (1986)
- CZ-2600S (1986)
Phase Distortion (PD) synthesis
Casio’s Cosmo Synthesizers — to give them their full title — used the in-house developed Phase Distortion (PD) sound source together with traditional analog modelling. It had similarities to Yamaha‘s proprietary FM synthesis.
PD works by distorting the phase angle of a sine or cosine wave written into a ROM when read, resulting in a variety of waveforms. The pattern of the distorted reading phase angle determines the DCO (digitally controlled oscillator – the digital equivalent of an analog VCO — voltage controlled oscillator) while the amount of distortion is determined by the momentary value of the DCW (Digitally Controlled Wave) – the digital equivalent of an analog VCF (Voltage Controlled Filter).
Casio explains the concept in several of the CZ owner manuals, captured below.
To keep costs down, Casio used a digital synthesis without filter, rather than analog subtractive synthesis with filter. This meant the sound was considered thinner than that of an analog synth. Phase distortion was used to simulate an analog filter.
There were eight waveforms in total:
- standard sawtooth
- square
- pulse
- double sine
- half-sine
- 3x simulated filter resonance
- resonant sawtooth
- triangle
- trapezoidal
Models in Depth
CZ-101 (1984)
An early entry in the CZ octet of keyboards is the CZ-101, launched in 1984. It was Casio’s first real entry into synthesisers rather than simple home keyboards.
It had 49 mini keys (four octaves) with no touch sensitivity or aftertouch. It could play eight notes of polyphony if used with a single DCO, or four with two DCOs — a common trait across the CZ line.
Sixteen presets, sixteen internal programmable memories and 16 extra per option RAM cartridge, it featured a programmer section for handling these, plus a parameter section for changing many aspects of the sounds. Rudimentary effects included portamento and vibrato.
The CZ-101 was one of many instruments adopting the MIDI standard, and indeed all eight models featured MIDI in and out ports.
The CZ-101 had a pitch bend wheel, was without speakers, so needed to be connected to headphones or line level equipment to hear anything. It had no pedal inputs and could be powered from AC or batteries.
CZ-1000 (1984)
The CZ-1000 is effectively the full size keyboard version of the CZ-101, with the same specifications and capabilities. Although the panel is more colourful than its smaller sibling, it has the same functionality.
CZ-5000 (1985)
The CZ-5000 is a full-size 61 key (five octave) model with 32 fixed and 32 writable memories, 16 note polyphony (1 DCO) or halved to eight (2 DCO). As well as the programmer and parameter editing, it features an eight track recording sequencer for up to 3,5000 notes in real time or 7,000 in manual mode, which is a form of step entry.
As with most of the CZ line, a cartridge slot allows for additional sounds to be saved and loaded, but it also includes a cassette interface for saving timbre and sequencer data.
No speakers, so audio and headphone outputs are provided, along with jacks for both a sustain and a volume pedal, as well as MIDI in/out and power.
CZ-1 (1986)
Control wise, the CZ-1 is a step up as it’s the only model in the range to feature velocity and aftertouch-enabled keys — 61 full sizers. It also has both a pitch bend and modulation wheel, as well as support for sustain and volume pedals — this makes its sounds vastly more controllable in real time, and puts this model at the top of the CZ pile for functionality.
It doesn’t have the onboard sequencer of the CZ-5000, but with MIDI support it made quite a formidable controller keyboard for its time. It had 16 note polyphony with 1 DCO, 8 with 2, 4 when using tone mix, and one in solo (you know the drill).
It could save out to RAM cartridge or via MIDI SysEx.
CZ-230S (1986)
The CZ-230S — S for speaker, just the one — offered eight notes of polyphony (four with 2 DCOs), 100 preset voices, and 20 built in rhythm presets featuring 80 patterns including intros and fill-ins. It’s the only CZ to offer rhythms — the relatively low polyphony and technology of the time probably the reasons why it didn’t include additional accompaniment instruments, as would be found on most home keyboard instruments of the era and beyond.
Compared to the other models, the CZ-230S could be considered more of a consumer model — giveaways being the inclusion of more presets and the loss of virtually all the synth functionality. The CZ-230S is a bit of an outlier compared to the rest of the line, and perhaps would be better aligned with Casio’s Casiotone models.
Connectivity was limited to just a line out and headphone jack, power jack, MIDI in/out terminals, and the MT tape interface for save/verify/load of pattern and song data. I don’t know if the sounds were in any way stereo treated, but if they were, the single monaural speaker meant you’d only benefit from them if they were output to stereo speakers or headphones.
CZ-3000 (1986)
The CZ-3000 features 61 full-size keys (five octaves), 16 note polyphony (halved for 2xDCO use), and three play modes:
- Normal: lets you play the presets, create new sounds, apply effects, and save timbres to memory or RAM cartridge.
- Tone Mix Mode: allows mixing of any two timbres (echoes of Casio’s ToneBank system) with independent setting of each timbre level.
- Key Split Mode: Splits the keyboard into upper and lower portions for independent play of two timbres, with level and effect settings.
It had 32 preset, fixed voices on board, plus another 32 for user editing. Pitch been and modulation wheels, effects including portamento, modulation depth and chorus control, timbre data saving to RAM cartridge, and a solo mode for monophonic playing of a sound.
CZ-2000S (1986)
The CZ-2000S was a Japanese-exclusive model based on the CZ-3000 with built in speakers. It was not sold directly in the US.
CZ-2600S (1986)
The CZ-2600S is another Japanese model, also based on the CZ-3000. It has stereo sound. It’s hard to find reliable images or data for this model.
Reception
Despite some of the limitations in lower cost instruments, the CZ line – particularly the more advance CZ-1 and CZ-5000 – were generally well received.
Despite being digital, sounds were warm, punchy and complex. CZs were considered easier to program and more intuitive than Yamaha’s DX7,
Improved control on the CZ-1 and onboard sequencing on the CZ-5000 was popular.
Lack of polyphony and some editing controls are cited, but it’s worth noting that some of these criticisms are seen through a modern lens, rather than considering what was available and affordable in the mid-80s.
The Casio CZ line may have not had quite the legacy of the DX line, for example, but they are fondly regarded, sought after by collectors, and take an important place in synthesiser history.
Notable Musicians Using CZ instruments
Notable musicians using Casio CZ synths included:
- Vince Clarke from Erasure/Yazoo/Depeche Mode — used multiple CZ-101s.
- Moby — CZ-101
- Richard Devine (sound designer)
- Steve Roach (ambient producer) — CZ-101
- White Town — CZ-101
- Kitaro
- Yuko Hara
- Hiroyuki Namba
Other anecdotal users include Carly Simon, The Eurythmics and Jean Michel Jarre.
Posters & Ads
Some of the info and promo posters and ads for Casio CZ synths.
Casio CZ brochure page 2
Where to Buy Casio CZ Models
All Casio CZ models are now over 40 years old, so it is difficult to source reliable, decently priced instruments in the range.
Buying vintage keyboard instruments can be tricky. You’re usually reliant on previous owners who list their music keyboards on various online marketplaces. There’s a certain level of trust involved that what is being described is accurate, and you’ll receive something which suits your need.
You need to be realistic here. The chances of finding mint condition — even fully working — instruments in this category diminishes with age. Those which do stand up to the ravages of history may well come with a hefty price tag. This is especially true of some of the cheaper models in the CZ range, which had questionable build quality and may now have broken plastic keys at the very least.
Nevertheless, you can try various sites — unlikely Amazon but there are many general listings on eBay. Alternatively try Reverb which is more of a specialist music retailer. You’re still primarily relying on the integrity of third-party sellers though.
Far less likely, though not impossible, is finding old keyboards in thrift/charity stores, or local/Facebook marketplace listings. The upside is that a lot of people won’t place any significant value on “an old keyboard” — the downside is that you’re less likely to strike gold in your locality, and you could still pick up and pay for rubbish.
Where to Repair Casio CZ Models
Repair is another tricky issue and not one we can cover in detail here.
If you can work out the nature of the repairs required, and what’s involved, then you could go about finding spares. eBay and Reverb sell spare parts but it still comes down to the luck of the draw.
Some repairs may involve fairly standard electrical part replacement – capacitors and such like – which could be more easily sourced. Other items, like sound chips and processors, could be nearly impossible to find now, unless you can find an old non-working instrument to use for spare parts — and so long as the reason it’s not working isn’t the same reason as yours.
