There are many free plugins on the internet. Some portals, like KVR, even have a plugin search engine that lists nearly 1,400 free instruments. Some are very old, or are poor quality or too basic, but there are also many very good and competitive with the commercial ones.
But … why free? Some plugins are versions with fewer functions than the commercial versions; others are made by developers who want to contribute to the community; and others, because developers are hesitant to pay the (sometimes high) price of commercial licenses of the programming frameworks they use, so the only option they have is to give it free.
In the following list we propose the crème de la crème, the best we have found. The approach we have followed is to have versions for Mac and PC (vst, vst3 and au), that are more or less recent (or updated frequently), of good quality and … free!
A monster to sound design. Discover how warping the harmonic makeup of a wavetable can completely create a new set of sounds. Stretch, shift, smear and skew harmonics up, down and around the spectrum to explore new timbres and create sounds you didn’t think possible with wavetables.
See how everything works while you play in this visual synth. Vital has animated graphical displays when you need them. Everything moves in real-time so you can see what’s going on behind the scenes.
Quickly design sounds with an optimized drag-and-drop modulation workflow. The modulation preview gives you an idea of what things will sound like before you drop the connection. With this, you can try modulating different destinations by dragging around the screen.
Pendulate is Generate’s litle brother, a monosynth powered by what the creators call a ‘chaotic oscillator based on a double pendulum’. The result is an oscillator that can smoothly fade from a sine wave to total chaos, with an expanse of territory to explore in between. Then is matched with a wavefolder and low pass gate, inspired by the ideas of Don Buchla. These three modules plus a lot of modulation options combine to make expressive sounds.
Although the square knobs and background animations (that you can turn off) can make the GUI a bit annoying or confusing, Pendulate can create quite original sounds.
This is the oldest on this list, but it is updated frequently (there are many contributors involved) and with a ton of features: subtractive synth with classic, FM and wavetable oscillators, powerful modulation, hundreds of presets, MPE enabled, skinnable … Each patch has 2 instances of the engine that can be layered or split, so the options of sound design are amazing!
It might seem a bit overwhelming with all those sliders, but it’s the price of owning this beast. Just keep in mind that it was previously sold as a commercial product for $99 and now, being open source and with all these features, it deserves to be on this list.
4 operators that can be arranged in the classic 8 FM algorithms to create a wide variety of sounds, from the typical 90s games music to more complex, warm and organic sounds. The operators can be the common sine, saw, triangle and square, or 8 classic waveforms emulated from the Yamaha TX81Z.
Each operator has got a separate amplitude envelope generator supporting the classic 5 point TX envelopes. These envelopes have been modeled to mimic the TX characteristics.
This gem is a recreation of Moog’s Realistic MG-1 synthesizer, which was one of the best-selling synthesizers in the ’80s thanks to its price and features (although it lacked pitch and mod wheels).
It’s an analog subtractive synthesizer with unique polyphonic oscillator section, “bell tone” ring modulation, glide, auto repeat note triggering, oscillator sync… In addition, it has been upgraded with a number of improvements that expand its capabilities.
From the creator of Vital (Matt Tytel), Helm is his previous job, but they are not comparable, as they are different types of synthesizers and Helm is 4 and Vital is less than 1 year old. With a GNU license, you can even download the source code to learn from it or change it.
The most important thing is how easy it is to use, even for newbies; It is also quite easy to add various types of modulation to many parameters. You can get really great sounds with very little effort. It’s very straightforward going from a very basic waveform to a complex one in just a few steps.
Another worthwhile open-source project! In brief, it’s “just” 3 oscillators, two filters, envelopes & LFOs programmable via a modulation matrix, amp, and 4 effects. In a pseudo-modular way, in this 24-voice polyphonic synth you can add different types of oscillators (even you can draw your own waveforms or shapes), a lot of filters (like the analog Moog-ladder or the Korg-35), and then… modulation.
And here, in the modulation matrix is where most of the magic happens. You can go crazy with 4 envelopes (amp, mod, filter, global), 4 LFOs, XY pad, arpeggiator, random generator, or even using the oscillators… After, there are four effects (delay, chorus, phaser and flanger but surprisingly… no reverb!).