Apps similar to Kushview Element include Carla, which is free and open source. Other options are Giada, DDMF Metaplugin, Reaktor and Light Host. You can choose from more than 10 Music Production Apps like Kushview Element for Windows, Mac and Linux.
Carla is an audio plugin host, with support for many audio drivers and plugin formats. It has some nice features like automation of parameters via MIDI CC (and send output back as MIDI too) and full OSC control.
Giada is a free, minimal, hardcore audio tool for DJs, live performers and electronic musicians. Just pick up your channel, fill it with samples or MIDI events and start the show by using this tiny piece of software as a loop machine, drum machine, sequencer, live sampler or yet...
Italy
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Metaplugin is a plugin that loads other plugins. As simple as that. Build your own effect networks with this plugin wrapper using any VST/VST3 (and AU, if you’re on Mac) effect you already have on your harddisk.
GermanyEU
Native Instruments Reaktor is a virtual, modular synthesis platform. REAKTOR also provides a platform for modular synthesis in the form of Blocks – a range of sound generating and sound shaping modules.
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A minimalistic VST host. Holds up to 4 VSTs. Allows for multiple instances (see how on GitHub). If you try to load an unregistered plugin, it may fail. Register somewhere else, then load it. If the sound clicks a lot, increase the buffer size or switch to Direct Sound in Audio...
United States
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A VST (plus AudioUnit on OSX) plugin host designed for live use. Based on the JUCE 'audio plugin host' code, heavily modified to better suit my purposes.
Cantabile is a music workstation for live performing musicians. Build your ideal rig - one that leaves you free to focus on giving your best performance.
SAVIHost lets you basically turn a VST instrument plugin into a standalone app. It's a very simple VST host that loads up a similarly named VSTi dll file and lets you interact with the plugin as if it's been loaded into a DAW complete with keyboard and extensive options...
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Plogue Bidule is a modular audio software with full VST, Audio Unit and Rewire support.
Canada
Live, modular sound design environment that enables a user to combine, split, layer and chain their VST instruments and FX.
United Kingdom
NanoHost is not a synthesizer. It is a free, minimalist host application for Windows that can load VST-synths. Furthermore, it can act as a wrapper which converts VST-synthesizers into standalone applications.
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