Kid3 tagger can edit the ID3v1 tags and all ID3v2 frames in MP3 files and the tags in Ogg/Vorbis and FLAC files in an efficient way. It is easy to convert between ID3v1 and ID3v2, set the tags of multiple files to the same values and generate the tags from the file name or vice versa. Import is possible from freedb.org, MusicBrainz, and other sources of track data.
JFreeChart is a chart library for the Java platform that supports a wide range of charts including pie charts (2D and 3D), bar charts (horizontal and vertical, regular or stacked, with optional 3D-effects), line charts, XY plots, scatter plots, time series charts, high/low/open/close charts, candlestick plots, Gantt charts, Pareto charts, combination charts, and more. It is suitable for use in applications, applets, servlets, and JSP.
Kwave is a 24-bit sound editor that allows simple operations, such as cut, copy, and paste. Some more effect functions with little complexity (Simple Filtering, Delay) are also implemented. More sophisticated analysis functions (spectrograms, sonagrams, pitch determination) are underway or partially done.
AeonWave-OpenAL is a thin OpenAL emulation layer that uses AeonWave to create one of the fastest rendering OpenAL implementations available. OpenAL is a cross-platform 3D audio API appropriate for use with gaming applications and many other types of audio applications. Its API style and conventions deliberately resemble those of OpenGL.
AeonWave is a cross platform, hardware accelerated, multi-threaded, and versatile stereo and 4D audio mixing library. By combining hardware accelerated rendering and a low memory footprint the library can handle almost any situation, from virtual synthesizer apps for smart phones to immersive simulation. It has a small, easy to use, fault tolerant, and consistent API, low latency support by using hardware acceleration, simultaneous support for stereo and 4D audio, audio frames with sub-mixing capabilities, support for stereo and 3D audio effects and filters, and a Freeware supplemental OpenAL implementation.
DR14 T.meter is a commandline tool for computing the Dynamic Range of your music according to the procedure used in the offline meter released by the Pleasurize Music Foundation. It is very useful to measure how loud your music is and to understand that a good quality album always has a good dynamic. It's also useful for understanding the effects of the so-called loudness war.
Music Player Daemon (MPD) is a server that allows remote access for playing music in various formats and managing playlists. It makes a great desktop player with frontend options (Qt, GTK, ncurses, Windows, and Web clients are available). It is also appropriate as a console player that is scriptable, and is especially useful if X is restarted frequently. A set of rapid development tools for clients are being developed and include a C library, Python module, PHP class, Perl module, and Java Class. The goals are to be easy to install and use, to have minimal resource requirements, to be stable and flexible, and easy to interface.