DSP.audio is described as 'Web-based editor with live tools to assist with digital signal processing in JavaScript. The editor automatically generates on-screen controls for parameters used in the base class meanwhile providing helpful audio analyzers as well as audio and MIDI input' and is an website in the development category. There are three alternatives to DSP.audio, not only websites but also apps for Self-Hosted. The best DSP.audio alternative is JSPatcher, which is both free and Open Source. Other great sites and apps similar to DSP.audio are eternal and WebAudioDesigner.
JSPatcher is a Visual Programming Language (VPL) in Max/PureData style on the web functioning as a playground for JavaScript Web APIs that lets you easily patch WebAudio native AudioNodes, import and patch external JavaScript modules and customize AudioWorklet DSPs with Faust.
WebAudioDesigner is a visual designer for Web Audio development. It provides a modular interface for building audio patches that can then be exported as JavaScript files.
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