Delta 6 by Hive Tunes


If you're looking for a free VST synth plugin to add some serious FM synthesis power to your DAW, Hivetune has released something worth checking out. Delta6 is a free six-operator FM synthesizer for Windows and macOS, designed to make complex FM sound design considerably easier to approach.


Unlike traditional FM synthesizers that rely heavily on predefined algorithms, Delta6 gives you an open modulation matrix, allowing you to create your own operator routing and experiment with different FM structures.


Delta6 is a 6-operator FM synth plugin built around six independently controllable operators. Each operator provides controls for its waveform, frequency ratio, fine tuning, level and ADSR envelope.

The synth includes five waveform choices:

  • Sine
  • Triangle
  • Saw
  • Square
  • Noise

This gives Delta6 considerably more sound-design flexibility than a basic sine-wave FM synthesizer.


The modulation matrix is arguably the most interesting part. Instead of choosing from a fixed collection of FM algorithms, you can connect the six operators yourself and visually see how modulation is flowing between them.


Features of Delta6

For a free synthesizer VST plugin, Delta6 offers a surprisingly complete feature set.

You get up to 16-voice polyphony, along with a monophonic legato mode and adjustable glide. There's also velocity sensitivity and a Drift control that introduces subtle pitch variation for a less sterile sound.

Operator 6 includes a dedicated feedback control, which can take its sound from a relatively clean waveform toward increasingly aggressive and chaotic textures.

The built-in effects section includes reverb and three chorus modes, adding some instant space and movement to your patches.


Quick Sound Design With the Dice Button

Don't know much about FM synthesis yet? Delta6 has a clever solution.

Its dice button can generate patches based around different sound categories such as pads, plucks, keys and leads. Instead of completely randomizing every parameter, it creates a more usable starting point by generating appropriate envelopes, ratios and modulation routing.

That's particularly useful for beginners who want to learn FM synthesis by experimenting rather than starting from a blank patch.


Free Version vs Complete Edition

The free version of Delta6 includes 20 presets and is fully featured. If you want a larger factory library, Hivetune also offers the Complete Edition for $4.99, which expands the preset collection to more than 100 sounds.

The free version is therefore a pretty easy recommendation if you're building a collection of free VST plugins for music production.


System Requirements & Formats

Delta6 is available for 64-bit Windows 10 or newer and supports VST3 and standalone formats. On macOS, it requires macOS 11 or newer and supports VST3, AU and standalone operation, with native Intel and Apple Silicon support.


Download Hivetune Delta6 Free

If you're interested in trying a new free FM synthesizer plugin, Delta6 is available directly from Hivetune.

Download Hivetune Delta6

For producers who have always found traditional FM synthesis intimidating, Delta6's visual modulation system makes it a much more approachable way to explore FM sound design, basses, plucks, leads, keys and experimental synth sounds.


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