Casio HT-3000

Casio HT-3000 Image

The Casio HT and HZ series are a very interesting group of synthesizers produced from 1987-1991. They use a very specific form of sound generation called "SD Synthesis". Short for "Spectrum Dynamic" SD Synthesis has some things in common with the subtractive synthesis we know and love. The synth takes a waveform and runs it through a real analog VCF (filter). There are ADSR envelopes for the DCA and VCF that shape the sound. And there is an LFO just like on a standard subtractive synth, although this LFO only modulates pitch (vibrato) and volume (tremolo).

Where things get interesting however, is in the choice of waveforms available from the synth engine. There are 32 incredibly varied waveforms, some sound very nasal or narrow, some like saw or square waveforms, some with an odd metallic timbre, and some feature white noise. It's still a mystery exactly how these waves are created, but experts suggest they contain a number of harmonically-rich pulse waves at different octaves, as well as a ring modulator and an analog noise source.

To make things even more interesting, these waves have pre-programmed amounts of PWM and amplitude modulation built into them. For example, one SD wave could contain two pulse waves fading in and out at different times. But you don't have to understand all of this to get the best out of the synth. The mystery and modulation of it all means you can just pick a preset and change the waves around and see what happens. The synth sounds are in the same ballpark as other DCO-synths of the time, and can even sound a little PPG-like on a good day. The filter is a bit weak for bass but adds a nice swoosh to some sounds. There is also a nice chorus effect on board. Additionally, being a home keyboard, it has built-in speakers, a Drum Machine and an Auto-Accompaniment mode (the lower tone is used for accompaniment). The drum sounds resemble the Casio RZ-1 8-bit drum machine.

The low point of the synth is in the programming. You have one big clunky rotary dial and a list of two digit parameters to edit (e.g.: 10 will be cutoff, 11 is resonance) and these parameters are not listed on the panel, so you need the manual with you at all times! MIDI is present, but limited to just 3-channels and has no SysEx support. Kind of a bummer from a synth with such a tedious programming interface.

The HT-3000 has several brothers (also released in 1987). They include the HT-700, which has 49 mini-keys instead of the 3000's 61 full-size keys. It also has a big brother in the HT-6000, which is a 4 DCO, 8 VCF and 64 waveform monster! (And the HT-6000 lists the edit parameter codes on front-panel.) Now, as no one really knows about the HT-series, they go for very little money and can be a great tool in your synth arsenal for unusual sounds!

Lookup Casio HT-3000 Prices

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25 Visitor comments
October 29, 2011 @ 3:52 pm
Senor, you don't need to change the internal Battery. Put some Big batteries in it and it works.
Senor V
October 26, 2011 @ 2:30 am
On another note, mine may have a flaw, but maybe someone out there can concur. When I save an edited tone in one of the internal tone sources, the edited sound will be stored in memory when it's on, but I'll lose it when it's turned off. Is this normal? Is there an internal battery that needs changed? Thanks.
Senor V
October 25, 2011 @ 11:39 pm
Just picked up a HT 700 for $25. Very interesting little synth! The upper wave forms include sawtooth, square, two pulse waves, and a NES-like triangle waveforms, but the rest are these weird clingy bell-like sounds and overtones that remind me of the DX series. The lower sounds (used for accompaniment in the chord section) aren't too bad, especially when ran through the filter, and really gives the synth an 80s flare when jamming along with the gritty drum samples. The filter itself is also decent, but not superb. All in all, it's not great, but it's excellent for being a Casio.
gary markus vile
October 25, 2011 @ 5:16 am
got one today (25th of october) for $75 in perfect condition. definitely looks like a crappy home styled keyboard but i think the sounds are quite useful, especially for ARIEL PINK style recordings, for the price they are going for you'd be a dummy not to buy one, nice for preset surfing and you won't really die inside if some idiot spills beer on it during live play.
October 18, 2011 @ 11:54 pm
The video demo of the HT-3000 shown here is made by me.
If you visit my chanel on youtube you will find more demo's from the HT-700 en the HT-6000. I love these keyboards for there sound and character and they are dirt cheap!
The HT-6000 is the one to get, touchsensitive, 4 dco's, 64 waveforms and ringmod. it has a seperate ADSR for noise.
VSE Rating

It’s Good

User Rating

Rated 3.46 (150 Votes)

  • Check Price
  • The link above will take you to an eBay search for this synth to see active listings. If you don't find it there, try looking in our forum marketplace or post a wanted classified.
  • Specifications
  • Polyphony - 8 voices
  • Multitimbral - 3 parts: Upper tone, Lower tone, Drums
  • Oscillators - 1 DCO
  • Waveforms - Upper tone: 32 SD waves, Lower Tone: 16 SD waves, Noise generator
  • LFO - 1 LFO with 5 waveforms for the Upper Tone, 1 for the Lower tone. Modulates volume or pitch only.
  • Filter - 1 VCF resonant analog lowpass with ADSR envelope
  • Envelope - 1 DCA with ADSR envelope
  • Effects - Analog Chorus (3 types)
  • Patterns - Drums/accompaniment: 10 user patterns
  • Keyboard - 61 keys (no velocity). Mod and pitch wheels.
  • Memory - 30 preset, 30 user
  • Control - MIDI In/Out/Thru (3 channels only and no SysEx)
  • Date Produced - 1987 - 1991
  • Resources & Credits
  • Review by Alex Juno

    Original images from this site

    Reviewed September 2011

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