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.
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.
Faust AUdio STreams is an expressive functional programming language for realtime audio signal processing. The Faust compiler translates DSP specifications into efficient C++ code. A variety of platforms and plugin formats are supported. A single Faust specification can be used to easily generate JACK and ALSA applications, as well as LADSPA, MAX/MSP, PD, Q, SC, and VST plugins. In addition to C++ code, the Faust compiler can also generate SVG block-diagram representations as well as XML descriptions.
AlsaPlayer is a new PCM player written with the ALSA sound system in mind. It also includes support for JACK, OSS, NAS, and ESD. It makes extensive use of multi-threading and supports OGG, MP3, WAV, CDDA (CD Digital Audio), MOD, S3M, IT, and many other input types. Features include a real- time effects stream, variable speed/pitch control, SHOUTcast/icecast streaming support, multiple active visual scopes, command line mode, playlists, plugin architecture, low-latency mode, and more.