Zoë Blade's notebook

Yamaha DX21

DX21 tech specs

  • Released: 1985
  • Price: £685[1]
  • Clearance price: £459[2]
  • Company: Yamaha
  • Type: FM synthesiser
  • Polyphony: 8 voices
  • Timbrality: Duotimbral
  • Operators: 4
  • Audio out: Stereo pair
  • Control: MIDI
  • Storage: Cassette tape, SysEx[3]
  • Display: 16×2 character LCD
  • Features: Chorus
  • User programs: 32
  • Preset programs: 128

The DX21 was an FM synthesiser made by Yamaha in 1985, followed the next year by two minor variations, the DX27 and DX100.

It was designed to be much cheaper than the DX7, which is good. As a result, it's also much simpler than the DX7, which, in my opinion, is even better.

Most notably, it has only four operators for each of its eight voices, less than the DX7's six operators for each of its sixteen voices.

Yamaha DX21 envelope graph
Yamaha DX21 envelope graph

Its envelope generators are simplified too, only slightly more complex than the popular ADSR variety. This is arguably a good thing when you're trying to wrap your head around programming it.

Compared to a regular ADSR envelope generator, essentially the sustain can also slowly fade out, offering more realism. Only organs and synthesisers have an external energy source that can sustain a note indefinitely. All other instruments play notes that slowly fade with entropy.

Even the amount by which higher pitches can attenuate each operator has been simplified, dispensing with the choice between linear and logarithmic scaling either side of an arbitrary break point in favour of a single value. Sorted. Similarly, higher pitches can still speed up each envelope generator, but only with half the precision.

Even the all-important frequency ratio of each operator is more limited, giving the user four different sets of sixteen mathematically related values to choose from.

Which is all to say, the DX21 range is greatly simplified from the DX7 range... which is arguably a very good thing, considering that learning FM synthesis is complicated enough as it is, without having to learn about things like break points at the same time. I don't think the DX21 range is significantly more limiting, so much as significantly more fathomable.

Having said that, "it's less complex than a DX7" isn't saying much. The DX21 and its siblings are still more than versatile enough to create a wide variety of sounds, and for enthusiastic sound designers to lose themselves for months on end learning to do so.

As with almost all hardware FM synthesisers, its small interface warrants using an editor/librarian such as 4-Op Deluxe.

The DX21 series was later superseded by the TX81Z series. This added a few bonus features, while retaining full backwards compatability if you don't need them.

DX27

DX27 tech specs

  • Released: 1986
  • Price: £499[1]
  • Company: Yamaha
  • Type: FM synthesiser
  • Polyphony: 8 voices
  • Timbrality: Monotimbral
  • Operators: 4
  • Audio out: Stereo pair
  • Control: MIDI
  • Display: 16×1 character LCD
  • User programs: 24
  • Preset programs: 192

The DX27 was a cheaper version, missing the DX21's built-in chorus effect, its second timbre (its keyboard split), and the second row of its LCD.

DX100

DX100 tech specs

  • Released: 1986
  • Initial price: £349[4]
  • Clearance price: £279[5]
  • Company: Yamaha
  • Type: FM synthesiser
  • Polyphony: 8 voices
  • Timbrality: Monotimbral
  • Operators: 4
  • Audio out: Stereo pair
  • Control: MIDI
  • Storage: Cassette tape, SysEx
  • Display: 16×1 character LCD
  • User programs: 24
  • Preset programs: 192

The DX100 was an even cheaper version, seemingly designed to compete with Casio's typically downmarket CZ-101. Both have four octaves' worth of miniature keys, a pitch bend wheel at the back instead of the front, hooks for a guitar strap, and the ability to run on batteries. In other words, both are designed to work as keytars.

Although the DX100 doesn't look as professional as Yamaha's other FM offerings, it was used by several notable musicians, including The Belleville Three, and the more prominent members of the Warp roster. At roughly half the price of the DX21, and with almost all its features, it was a good choice for someone starting out at the time, as many were.

Quotes

DX100

I love the "Solid Bass" preset. I can tell you now, 'cos I've used it so much that I don't care if somebody else uses it. I don't really need sounds in a keyboard, I just need a trigger mechanism for the samples. I don't use many synth sounds, 'cos to me they sound fake and they sound too clear. "Solid Bass" is kind of dirty.

— Mark James (The 45 King), 1989[6]

I've had Matrix 12 filtering applied to the [DX100] to give it a completely different feel. The board was almost destroyed in the process. It was like "let's see what we can get away with". It breaks down a lot, but when it works it works, and it's my sound, it's part of the Rhythim Is Rhythim sound. And, like my American Express card, I don't leave home without it... You're not going to get beautiful string sounds out of it, but for bass sounds I've got the fat filter sound. In a little keyboard like that, it's so funny.

Derrick May (Rhythim Is Rhythim), 1990[7]

It's really noisy, and some of the presets are so horrible, but the bass sounds are wonderful, especially on things like the "wood piano". By mixing that with the Minimoog, you can get the ideal bass sound, with both warmth and bite.

— Jon Marsh, The Beloved, 1993[8]

It's good for basslines. It appears on at least three of our tracks, including Halcyon. Other people still use it. When I hear it, I just think "Ah! Solid Bass!"

— Paul Hartnoll, Orbital, 1993[9]

Everyone thought the DX100 was amazing to do basslines, but we didn't do that for ages. It seemed like there was so much more to them to explore, like they're good for brassy, reedy sounds.

— Sean Booth, Autechre, 2004[10]

Notable users

DX21

DX27

DX100

See also

References

  1. "Music Village" Music Village (Vendor), Music Technology, Feb 1987
  2. "Soho Soundhouse" Soho Soundhouse (Vendor), Music Technology, Feb 1988
  3. "DX21 manual" Yamaha
  4. "Soho Soundhouse" Soho Soundhouse (Vendor), Electronics & Music Maker, Mar 1986
  5. "Music Village" Music Village (Vendor), Music Technology, May 1987
  6. "45 Kingdom" Simon Trask, Music Technology, May 1989
  7. "Techno Rhythim" Simon Trask, Music Technology, Nov 1990
  8. "Dearly Beloved" Phil Ward, Music Technology, Mar 1993
  9. "[Unknown]" Dave Robinson, Future Music, Aug 1993
  10. "Autechre" Paul Tingen, Sound On Sound, Apr 2004
  11. "Synths and Stuff" Danny Wolfers
  12. "Strange Changes" Simon Trask, Music Technology, Dec 1991
  13. "~~ rephlex ~~ aphex ~~ drn ~~" Ben Middleton, alt.rave, Oct 1992
  14. "Aphex Twin SYROBONKERS! Interview Part 1" Dave Noyze, 2014
  15. "Future Shock" Simon Trask, Music Technology, Dec 1988
  16. "Aural Technology Redefined?" Simon Trask, Future Music, Jan 1995
  17. "AAA — Ask Autechre Anything — Sean and Rob on WATMM!" Sean Booth, We Are the Music Makers, Nov 2013
  18. Rendez-Vous Jean-Michel Jarre, 1986
  19. "Mixing up the motor city" Rob Green, The Mix, Apr 1995
  20. "Earth beats" Roger Brown, The Mix, Apr 1995
  21. "The Magic Circle" Phil Ward, Music Technology, Jun 1993
  22. "Music of Spheres" Nigel Humberstone, Sound On Sound, Apr 1994
  23. "The Techno Wave" Simon Trask, Music Technology, Sep 1988

Reviews

DX21

DX27 / DX100

DX100

Deep dives

Downloads

Documentation

FM synthesisers: Yamaha DX7 | Yamaha DX21 | Yamaha TX81Z