SILICONAntiques
Silicon Antiques › Mellt FM-1
Free FM synth · macOS · AU, VST3, Standalone

MelltFM-1

A 23-voice, 7-operator, stereo FM synth. Every operator reads a wavetable, and every algorithm lives on a pin matrix.

mellt · Welsh for lightning

  • 7operators
  • 23voices
  • 12algorithms
  • 2,299pins
  • 11LFOs
Get Mellt FM-1 free Full specs

Free for macOS. AU, VST3 and Standalone. Windows: not yet.

Mellt FM-1 panel: the 21 by 111 pin matrix across the top, the FM routing board with algorithm 4, Pairs + Sine, and seven operator envelopes all set to Trapezoid along the bottom
The story

Our journey began with Mellt.

The first Silicon Antiques instrument, and the one that proved the idea.

FM is often thought of as difficult to program. Our view is that most of that challenge lives in interface design.

It occurred to us that all of the algorithms on that famous FM synth from the 1980s could be represented easily on a pin matrix. Mellt lets you choose an algorithm from the traditional diagrams or on a matrix. For many, this simple change of visualisation is a breakthrough: every operator relationship is in front of you at once, instead of behind a number.

But Mellt takes this concept further by also representing all the interrelations between the operators in the chosen algorithm on a matrix.

In fact it takes it further still: every modulation source in Mellt can be patched to every modulation destination via the matrix.

Try it for yourself. Yes, Mellt can make all those classic piano, glockenspiel, bell and glass tones we all associate with FM. But we think you'll find the interface takes you in new, more experimental, directions.

Listen

Three sounds, thirty seconds each.

Classic FMElectric piano, bells, glass. Audio coming soon.
Operators as wavetablesWhat happens when each operator reads a wavetable. Audio coming soon.
Followers and joystickMellt moving with a drum loop. Audio coming soon.
Things you didn't expect

Not your usual FM synth.

Every operator reads a wavetable

39 factory wavetables per operator, plus a User slot that imports your own WAV, AIFF or FLAC. Sine-wave FM is where it starts, not where it stops.

Algorithms as pins

Pick one of the 12 algorithms from a diagram, or click a connection on the routing board and Mellt jumps to the nearest algorithm that has it. Every operator-to-operator relationship is a pin you can see. All twelve, drawn.

Every pin is automatable

All 2,299 pins are host parameters, 2,666 parameters in all with the panel controls. Automate them, map them to a controller, morph a patch from your DAW's lane.

Eleven envelopes, eleven LFOs

Seven per-operator envelopes and LFOs, plus four global ones of each. Every stage of every envelope can be tempo-linked, not just the LFOs.

Filters on the followers, not the audio

Nothing filters the operators. Instead each of the three envelope followers has its own low-pass, high-pass or band-pass, so the follower listens to the part of the track you want it to.

No effects, no latency

Mellt is the pure engine. Nothing sits on the audio path after the operators but a DC blocker, so there's no look-ahead and nothing to compensate. Put your own effects after it.

Specifications

The numbers.

Everything on the panel, in one table.

SynthesisFM, 7 operators, each reading a wavetable
Algorithms12, selectable from a diagram or on the matrix: Stack; 4 + 3 Stacks; 3 + 2 + 2 Stacks; Pairs + Sine; Six Into One; Two Chains Into One; Stack Feeds Three; One Into Six; 5 Stack + Pair; Twin Branches; Binary Tree; Additive
Polyphony23 voices
Unison1 to 8
OutputStereo, with Spread per note. A mono bus is accepted and summed
Wavetables39 per operator, plus a User slot per operator that imports a WAV, AIFF or FLAC file
Oscillator syncOff / Hard / Soft. Operators 1 to 6 sync to the operator above
FiltersNone on the audio path. Each of the three envelope followers has its own filter: Off / Low-pass / High-pass / Band-pass
Envelopes11. Seven operator envelopes (ADSR or Trapezoid) and four modulation envelopes with six modes (AD, ASR, ADSR, AHDSR, DADSR, Trapezoid). Every stage of every envelope can be tempo-linked
LFOs11. Seven per-operator and four global. Six shapes (Sine, Triangle, Saw Up, Saw Down, Square, Sample & Hold), tempo sync
Envelope followers3, fed from the Input and Sidechain buses
Other modulatorsJoystick X/Y with motion recorder; 4 macros; FM Depth performance knob; vibrato with a mod-wheel option; MPE
EffectsNone
Voice modesPoly / Mono / Legato, with glide
MPEYes, on/off with a note bend range
BusesStereo output. Two stereo inputs, Input and Sidechain, feeding the envelope followers
MIDIMIDI Learn, so your existing controllers give hands-on control
Presets15 factory presets
FormatsAU, VST3 and Standalone. macOS
The matrix

21 sources. 111 destinations. 2,299 pins.

Every source can reach every destination. Each pin has its own amount and is a host parameter. The destinations sit on four pages of the panel.

  • 21sources
  • 111destinations
  • 4pages
  • 2,299pins, all automatable

Sources 21

  • LFO 1
  • LFO 2
  • LFO 3
  • LFO 4
  • Env 1
  • Env 2
  • Env 3
  • Env 4
  • Follower 1
  • Follower 2
  • Follower 3
  • Velocity
  • Release Velocity
  • Aftertouch
  • Slide (CC 74)
  • Joystick X
  • Joystick Y
  • Macro 1
  • Macro 2
  • Macro 3
  • Macro 4

Destinations 111, on four pages

Sound · 33

  • Pitch (all)
  • Volume
  • Feedback
  • Position (all)
  • Pan (all)
  • Operator 1 to 7: Pitch
  • Operator 1 to 7: Level
  • Operator 1 to 7: Position
  • Operator 1 to 7: Pan

LFOs · 22

  • LFO 1 to 4: Rate
  • LFO 1 to 4: Depth
  • Operator LFO 1 to 7: Rate
  • Operator LFO 1 to 7: Depth

Envelopes · 28

  • Env 1 to 4: Delay
  • Attack
  • Hold / On
  • Decay
  • Sustain
  • Release
  • Off

Operator envelopes · 28

  • Operator 1 to 7: Attack
  • Decay
  • Sustain / On
  • Release / Off
What it sounds like

Everything you expect from FM. Then the rest.

  • electric pianos
  • glockenspiels
  • bells
  • glass
  • mallets
  • basses
  • brass
  • plucks
  • pads from wavetable operators
  • sounds that don't have names yet

Fifteen factory presets get you started. The matrix is where you'll spend your time.

The panel

A walk round Mellt FM-1.

The Vintage panel, as it ships. Click any shot for full size.

Mellt FM-1, OP ENVS view
OP ENVS. Seven operator envelopes, every one a trapezoid. The E. Piano preset, with its pins in the matrix.
Mellt FM-1, OPERATORS view
OPERATORS. Seven operators: wave, ratio, fine, position, pan, level. Each one reads a wavetable.
Mellt FM-1, As it opens view
As it opens. The Init patch: an empty 2,299-hole matrix and the routing board on algorithm 2, 4 + 3 Stacks.
Mellt FM-1, LFOS view
LFOS. Eleven LFOs: one per operator and four global. Six shapes, tempo sync.
Mellt FM-1, ENVELOPES view
ENVELOPES. The four modulation envelopes, six modes each, every phase syncable.
Mellt FM-1, FOLLOWERS view
FOLLOWERS. Three envelope followers, each with its own filter and bus choice.
Mellt FM-1, Modulation board, LFOs page view
Modulation board, LFOs page. The matrix destinations change by page. Here, LFO rates and depths.
Mellt FM-1, PERFORM view
PERFORM. The oscilloscope, the joystick with its motion recorder, four macros and FM Depth.
Mellt FM-1, Preset browser view
Preset browser. Fifteen factory presets to start from.
Mellt FM-1, On-screen keyboard view
On-screen keyboard. Standalone or plug-in, with a keyboard when you need one.
Questions

Before you download.

Is Mellt FM-1 really free?

Yes. Mellt is a free download. We ask for your email address so we can send you the link and tell you about new instruments.

Does Mellt run on Windows?

Not yet. Mellt is macOS only for now, as AU, VST3 and Standalone.

Can I automate the pin matrix in my DAW?

Yes. Every one of Mellt's 2,299 pins is its own host parameter, so any pin can be automated or mapped to a controller.

Does Mellt have built-in effects?

No. There is nothing on Mellt's audio path after the operators except a DC blocker, so it adds no latency. Put your own effects after it.

Can I load my own wavetables?

Yes. Each of the seven operators has a User slot that imports a WAV, AIFF or FLAC file, alongside the 39 factory wavetables.

Does Mellt support MPE?

Yes. MPE can be switched on and off, with a configurable note bend range.

Free download

Get Mellt FM-1.

Free for macOS. AU, VST3 and Standalone.

Get Mellt FM-1 free
The other two
Tant KS-2Karplus-Strong string synth. 23 voices, 2 filters per voice, 6 effects. Tonnau WT-3Wavetable synth. 3 oscillators, Era per oscillator, 6 effects.