Microtuning Vintage Hardware Synthesizers

What is microtuning?

Microtuning is the given (by western musician) to tuning systems outside of 12 equal divisions of the octave (12EDO) using in most western music. Other tuning systems have been used throughout history outside of the wes in places like Latin America, Africa, Eastern Europe, the Middle East and Asia using acoustic instruments. Most synth manufacturers don't include this feature due to the pervasiveness of 12EDO supported by western music education, music theory programs in higher education, the piano business, the sheet music business, the need for guitars to be in tune with pianos, etc.

What does microtonal electronic music sound like?

Here are some examples of microtonal electronic music:

Microtuning with vintage hardware synths and samplers

There are a handful of vintage synths and samplers that have microtuning as a native feature:

  • Yamaha TX802
  • Yamaha TX81Z
  • Yamaha DX11
  • Yamaha DX7IIfd
  • Yamaha DX7S
  • Ensoniq EPS, EPS-M, EPS-16 Plus, EPS-16 Plus Rack
  • Ensoniq ASR-10, ASR-10R, ASR-88

These synths have quasi-microtonal features:

  • Ensoniq ESQ1, SQ80 by modulating one of the OSC with KEYB2 and setting it to a number other than 0 as explained on Modwiggler and Sound on Sound you can have various EDO tuings per patch.
  • Roland D50/D550 using the Key follow setting:
    • 1 = 12 EDO
    • 7/8 = 13.714 EDO
    • 3/4 = 16 EDO
    • 5/8 = 19.2 EDO
    • 1/2 = 24 EDO
    • 3/8 = 32 EDO
    • 1/4 = 48 EDO
    • 1/8 = 96 EDO
    • S1 = 2 cents sharp per octave up
    • S2 = 5 cents per octave

Many Korg synths starting with the M1/M1R can have each of the 12 notes detuned up or down 50 cents independent of each other, and these repeat for each octave. This is not full microtonal but it can provide a series of pitches to work with that do not sound like 12EDO.

Multi-Temperament Scales is alternate OS for Ensoniq Mirage that allows you to choose a few other tuning systems.

"Retuning" with pitch bend

Any multitimbral synth or sampler can be used microtonally with the pitch bend method where each new note is dynamically allocated to a different multitimbral part with just the right amount of pitch bend send before the note on. Each can import Scala tuning files and/or KBM files. The following tools will allow you to use this method with any multitimbral synth that responds to pitch bend and has an adjustable pitch bend range:

Set the patch on each part to the same patch, set each part to a different midi channel. The polyphony is limited by the number of parts even if it is less than the polyphony. For example, a Nord Lead 1 expanded is 12 voices but since it is only 4 parts you will only get 4 voices of polyphony when using this dynamically allocated pitch bend method.

Lastly, any synths with "guitar mode," which are typically monotimbral can instantly be set up for the dynamically allocated pitch bend method mentioned above by enabling their guitar modes. This was originally for guitar midi pickups developed by Roland. Each string had its own midi channel since pitch bend effects all notes on the entire part. This would allow for string bends. By setting a synth to guitar mode it instantly sets a monophonic voice per parts 1 through 6 on midi channels 1 through 6. Monotimbral or multitimbral polyphonic synths that have guitar mode are:

  • Oberheim Matrix 6/6r/1000
  • Roland MKS70 (without Vecoven mod)
  • Roland MKS50
  • Roland MKS-30(with Kiwi 30 mod)
  • Casio VZ-8m

Other non-vintage synth related microtonal info