Open Source JavaScript Sound Synthesis Apps for Android

Standing Wave 3 is an ActionScript 3 audio library that provides high-level control over the Flash Player’s SampleDataEvent API for streaming audio output. It builds on the foundation of Standing Wave 2 but has been extensively refactored, with its core sample storage and manipulation routines rewritten using Adobe Alchemy for significant performance improvements. Originally derived from the audio engine used in the Noteflight Score Editor, the library allows developers to combine and chain together audio sources, filters, and sequences to create dynamic, real-time sound experiences. Supported audio sources include MP3s, WAV files, and algorithmic generators, while filters enable effects such as echo, equalization, and envelope shaping. The system is flexible enough to handle complex timing sequences of audio, making it suitable for advanced audio applications or interactive projects.

Just download the above zip file, extract it and then open the respective index.html file on your favourite internet browser and follow the instructions shown.

Transform pure innocent audio files, speech, music, etc into unholy demonic abominations. Audio Satanifier 666 is a fun easy-to-use browser-based tool forged in the pits of hell, for voice actors, musicians, sound designers, for memes, for creative projects or anyone else who want to twist their sound into something absolutely diabolical! Layperson friendly - you'll be able to apply cool effects to your audio file even if you know nothing about audio engineering. Theres also a Mini version that has a voice deepening that doesn't slow the speed of the audio. Its more focused on the "satan voice" filter, while the larger default version has 16 different filters you can mix and match. (Source code is included within the html file itself.)

SINE Isochronic Entrainer is a Free and Open Source Brainwave Entrainment application for PC, Android, and HTML5. Brainwave Entrainment is the practice of using sounds, visual stimuli or even electromagnetic fields to alter the frequency of brainwaves. It can be done for several reasons: people with insomnia can take great benefit from it, but it can also be used to improve your attention span, and even simulate the effects of some recreational drugs. The effect is not permanent, and fades away in less than a minute after the stimuli is removed. Isochronic tones are a commonly used aural stimuli for Brainwave Entrainment, consisting of short pulses of a sine wave, varying in frequency. Unlike binaural beats, isochronic tones can be played on speakers. The Player supports touchscreens and high resolution displays. Includes a graphical editor for making presets, with a manual.