Linux

Protoverb is an experimental reverb based on the idea of a "room simulator". Most algorithmic reverbs try to avoid resonances or model the reflections of sound from a rooms walls.
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LoudMax is a Look-Ahead Brickwall Loudness Maximizer Plugin with a clean transparent sound. It is designed to retain the original character of the music as much as possible even at high compression levels.
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Regency offers a novel method of synthesis, based off traditional phase distortion synthesizers...
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Among the features are pitch shifting on the feedback, asymetric ping pong, reverse delay, and more...
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Up to four modules can be added to any one of the four bands. As of writing, there are 16 modules available to choose from...
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The free Lost-Tapes effect plugin is based on tape emulation, but does not model any specific hardware model...
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PaulXStretch is designed for a radical transformation of sounds. It can turn audio into hours or days of ambient soundscape in a smooth and beautiful way.
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LibreArp is a free MIDI effect VST plugin that takes chords in the form of MIDI input and outputs so-called arpeggios based on the input chords.
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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.
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OS-251 is a pure digital lo-fi synthesizer plugin for Mac, Windows and Linux. Available in VST3 and AU plugin formats for free.
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Set out in a hardware compressor visual style, it won't take you long to get your sounds thumping with this. Featuring Ratio/Attack and Release/Sensitivity and Makeup controls this free compressor is available for Windows MacOSX and Linux.
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InstaLooper is a simple looper with five integrated FX for Mac, Windows and Linux (AudioUnit & VST, 64-Bit)
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