The Midium

Melbourne Instruments' description of the Melbourne Instruments DELIA 6-voice motorized morphing polyphonic synthesizer



DELIA is a bi-timbral polysynth inspired by the motorized control panel and voice architecture of the original Melbourne Instruments’ Nina. Delia introduces a 49-key velocity and aftertouch sensitive keyboard, new multi-mode analog filters, high pass and low pass resonance control, 3-stage overdrive, and even more modulation possibilities. 

The powerful combination of analog plus digital is harnessed by Delia’s unique 12 note mode, using 12 complete oscillator banks into the 6 filters, limiting note stealing without compromising the sound, and fully unleashing Delia’s bi-timbral operation.



DELIA’s true analog low pass filter is the heart and soul of the sound engine — warm, full and sweet or fearfully aggressive. It is complemented with a high-pass modelled ladder filter, which can be linked for bandpass and notch operation.



DELIA’s filters have an analog and a digital section per voice. The analog filter is the classic discrete transistor ladder filter offering a choice of 24dB or 12dB per octave operation. Prior to this filter is an analog variable overdrive circuit that can push the filter from normal operation to complete distorted collapse of the transistor ladder, adding richness, aggression and body to your sound. 

The HP filter is a digital transistor-level mathematical model of a 24dB ladder filter, based on the gold-standard Ebers-Moll transistor equations. This gives an almost perfect match to the response of the analog circuit, including the overdrive response, resonance and natural filter frequency variations.

The High Pass filter is less important sonically, so the choice of digital instead of analog reduces cost without compromise. Having the Low Pass filter second gives true analog character where it counts.

The filter is Multi-mode with 3 ways to configure. The High Pass and Low Pass cut-off frequencies are separately controlled with 2 knobs, so the overall operation can be High Pass, Low Pass or Bandpass. The separate HP and LP resonance controls offer flexibility to shape the sound including vocal-style formants. Delia’s LINK function locks the distance between the Low Pass and High pass knobs, setting a constant width Bandpass for both manual control and sweeps using the VCF envelope or other Modulation Matrix controls.



DELIA’s A/B Morph function lets you explore and sweep through timbres like no other. The A/B Morph sound is an actively calculated change in parameters between the A and B patches including the entire modulation matrix. This provides the ability to instantly create a new preset based on the Morph position that is neither the A or B patch, but instead a totally new sound. Morph is also a ‘MOD destination’, giving you even more creative control via Aftertouch, Mod Wheel and Expression.



DELIA inherits many of the acclaimed features of Nina, including 4-Quadrant Analog VCAs, Morphing, Digital Effects and Digital Wavetable Oscillator. Adding to these features are the inclusion of Sequencer Phrase Looping and Overdubbing, and the ability to assign your favorite effects parameter to the Effects Macro control.

Delia’s 20 modulation sources and 40+ mod destinations with unlimited slots gives sound designers an almost endless spectrum of sounds. Two digital effects processors paired with classic effects presets and the option to run in series or parallel. And with the ability to save more than 16,000 presets inspiration and artistry will never be limited.




  • True Analog Filters and stereo VCAs
  • 4 Oscillators per voice:
    VA Modelled VCOs, Wavetable, Noise/XOR/Aux
  • 6 Analog voice circuits with 12-note mode that retains 4 oscillators/voice.
  • Unlimited Modulation Matrix - 20 sources x 40 destinations
  • 3 x LFOs with variable shapes:
    Sine, Triangle, Square, Ramp up, Ramp down, Random)
  • 3 x Envelopes: VCA, VCF, AUX



  • Analog Low Pass Ladder Filter
  • 3-stage Analog Overdrive
  • Virtual Analog High Pass Ladder Filter
  • Separate High Pass and Low Pass Resonance control
  • HP/LP filter ‘LINK’ mode for Band Pass/Notch control
  • Selectable 12dB and 24dB slope for LP Filter


  • 2 x Effects Processors with parallel or series configuration
  • Stereo Digital Effects: Delay, Chorus, Reverb with classic Preset Algorithms



  • Extensive modulation matrix. 20 sources to 40 destinations. No bus count limitation.
  • Morphable modulation settings.
  • Quick to edit MOD mode. Select a source and dial in amounts instantly on control panel.
  • All MOD amounts are through zero (bipolar)
  • MORPH is a available as a Modulation destination



  • Morph between A and B patches to create new timbres.
  • Morph the entire patch including Modulation Matrix.


  • 2 layers for 4 Timbres when combined with A/B Morph
  • Controllable via MIDI channel and note ranges
  • User selectable number of assigned voices per layer
  • Optional linked note ranges across layers for quick keyboard splits & layering



  • 16-step Programmable Polyphonic Sequencer
  • Phrase Looper with overdub/layering
  • Sequences and loops are saved with presets and recallable



Audio Out

  • 2 assignable line level outputs.

  • Stereo main outputs with effects.

  • Headphone output.

Audio In

  • 2 TRS Balanced Line or CV Inputs.

  • CV +/-10V max. Analog gain and offset trim.

Device connection

  • 2 x USB-A host ports

  • 1 x USB-C device for DAW connection


  • In / Out / Through


  • Hackable Open Source software built on a powerful Raspberry Pi 4 running Elk Audio OS


  • Weight: 8.7kg (19.1lb)
  • Dimensions (length x width x depth): 810mm x 320mm x 140mm.
  • Metal construction