CLAM chordata analyses the chords in a song and allows you to navigate along the song while watching several views to get insight of chords and other tonal features. Its simple and handy interface is designed for players with an instrument at hand. This application is part of the CLAM framework.
Rubber Band is a high quality software library for audio time-stretching and pitch-shifting. It permits you to change the tempo and pitch of an audio stream or recording dynamically and independently of one another. Rubber Band is a library intended for use by developers creating their own application programs rather than directly by end users, although it does also include a simple command-line utility program that you can use for fixed adjustments to the speed and pitch of existing audio files.
RMP allows remote control over playing your music files on a Linux computer. The music can be controlled via a Web interface, a smart cellphone, iPhone, Blackberry, or through a command line shell interface. If you like the song, you can download it to your phone. It supports next, searching, and volume control.
mmq plays arbitrary audio files gaplessly and continuously without needing a predefined queue. mmq is an exercise in minimalism, so it is more about avoiding needless features than anything else. mmq may be used standalone or managed by a larger application. mmq is only configurable at build time. Currently, FLAC decoding and SALSA-lib audio output support are implemented.
jack-tuner is a musical instrument tuner that uses the JACK audio connection kit. It is a command line program, and it accepts many commands. The important ones are the tone and volume commands, which can produce any audible tone from 20hz to 20khz at a volume from 0 (silence) to 1 (loudest). It can also produce notes (for example, "tone D#" produces the note D#) over several octaves (for example, "tone C octave -1" produces the note C an octave below middle-C). It can also transpose notes (for example, "tone C > 5" produces G). There are commands to do microtonal tuning too. With multiple jack-tuner instances, you can tune chords. jack-tuner does not measure the note that an instrument is playing; instead you play the desired note with jack-tuner and tune your instrument by ear.
Packrat is a media collection manager application for Android. You can use it to add books, CDs, games, movies, etc. to your collection by scanning their barcodes and organizing them onto shelves. You can let Packrat organize your items into smart shelves, or manually stack items onto shelves of your own creation. You can also track items you don't have yet on a "wishlist" shelf.
Khövsgöl is a minimal, highly configurable music player and browser. It can easily handle very large collections of music. It's designed for the GNOME desktop, but can run well in other environments. It works fine as a standalone player, but can also be used to remotely control music daemons such as MPD.