TerminatorX is a realtime audio synthesizer that allows you to "scratch" on digitally sampled audio data (*.wav, *.au, *.mp3, etc.) the way hiphop-DJs scratch on vinyl records. It features multiple turntables, realtime effects (built-in as well as LADSPA plugin effects), a sequencer, and an easy-to-use GTK+ GUI.
Qsynth is a GUI front-end application for Fluidsynth. Fluidsynth is a command-line software synthesizer based on the Soundfont specification. Qsynth was built with the Qt4 toolkit using Qt Designer. Eventually it may evolve into a softsynth management application that allows the user to control and manage a variety of command line softsynths, but it currently just wraps the excellent Fluidsynth program.
Beast is a powerful music composition and modular synthesis application. It offers multiple input methods like multitrack, piano roll, and pattern editing and supports skins. On the technical side, it has a wide range of abilities like sequencing, unlimited undo/redo history, real-time synthesis with multiprocessor support, full duplex 32-bit audio rendering, precise timing down to sample granularity, on demand loading of partial wave files, on the fly decoding of various sample formats, aliasing free oscillators, and full Scheme scripting support.
ebook2cw is a command line program that converts a plain text file (like an eBook) to Morse code (CW) MP3 or OGG files. Morse parameters like speed and tone frequency, and audio parameters such as bit rate, sample rate, and quality can be changed by command line switches. It automatically splits and numbers the output files by chapters.
din is a software musical instrument and audio synthesizer. Bezier curves are used to draw and sculpt waveforms, create gating and modulation (FM and AM) patterns, and create delay feedback and volume patterns. You can also create an unlimited number of drones and sculpt their waveforms. It uses JACK to output audio, and supports MIDI, OSC and IRC bot for input. din can be extended and customized with Tcl scripts.
FluidSynth is a real-time software synthesizer based on the SoundFont 2 specifications. It can read MIDI events from MIDI input devices or files and render them to an audio device using SoundFont instrument banks. It can also play MIDI files. Other features include real time effect control and a powerful API for embedding FluidSynth in other programs.
orDrumbox is a fully-featured drum machine and audio sequencer that is pattern oriented, has an automatic composer, automatic sound assignations, custom drum kits, loop support, and the ability to import and export songs. Its main features are a pattern seqencer, a drumkit editor, a piano roll, a step sequencer, sound generation, soft synth, and the ability to import and export MIDI files and Wave files.