ReZound aims to be a stable, open source, and graphical audio file editor primarily for, but not limited to, the Linux operating system.

rezound.sourceforge.net
sourceforge.net/projects/rezound
github.com/ddurham2/rezound
ReZound aims to be a stable, open source, and graphical audio file editor primarily for, but not limited to, the Linux operating system.

rezound.sourceforge.net
sourceforge.net/projects/rezound
github.com/ddurham2/rezound
The Network Audio System is a network transparent, client/server audio transport system.
Features:
- Device-independent audio over the network
- Lots of audio file and data formats
- Can store sounds in server for rapid replay
- Extensive mixing, separating, and manipulation of audio data
- Simultaneous use of audio devices by multiple applications
- Used by a growing number of ISVs
- Small size
- Free! No obnoxious licensing terms
Cdrdao records audio or data CD-Rs in disk-at-once (DAO) mode based on a textual description of the CD contents.
Advantages of Disk-At-Once (DAO) Recording:
Recording in disk-at-once mode writes the complete disc, i.e. lead-in, one or more tracks and lead-out, in a single step. The commonly used track-at-once (TAO) mode writes each track independently which requires link blocks between two tracks. Older CD-recorder models forced a two second pause (pre-gap) between two tracks whereas newer models allow adjusting of the pause length in TAO mode reducing the number of link blocks to a minimal amount. However, with TAO it is generally not possible to define the data that is written in pre-gaps. But exactly this feature makes audio CD recording interesting, e.g. by creating hidden bonus tracks or track intros in pre-gaps like it is common habit on commercial CDs. Finally, DAO recording is the only way to write data to the unused R-W sub-channels for e.g. CD-G or CD-TEXT.
Features:
- Full control over length and contents of pre-gaps (pause areas between tracks). Pre-gaps may be completely omitted, e.g. for dividing live recordings into tracks.
- Control over sub-channel data like:
- catalog number
- copy, pre-emphasis, 2-/4-channel flags
- ISRC code
- index marks
- Support for exact audio, data and mixed mode CD copying.
- Support for R-W sub-channel writing.
- Tracks may be composed of different audio files supporting non destructive cut.
- Accepts WAVE and raw audio files.
- CD-TEXT reading and writing with drives that support it.
- CDDB access to automatically create CD-TEXT data.
- Support for on-the-fly copying.
cdrdao.sourceforge.net
github.com/cdrdao
wiki.hydrogenaud.io/index.php?title=Cdrdao
en.wikipedia.org/wiki/Cdrdao
Frontend (GUI):

cdrdao.sourceforge.net/gcdmaster
DarkIce records audio from an audio interface (e.g. sound card), encodes it and sends it to a streaming server.
DarkIce can record from:
DarkIce can encode in the following formats:
DarkIce can send the encoded stream to the following streaming servers:
jack-keyboard is a virtual MIDI keyboard – a program that allows you to send JACK MIDI events ( 😉 play using your PC keyboard). It’s BSD-licensed. User interface is GTK-based.

fmedia is a fast media player/recorder/converter for Windows, macOS, Linux and FreeBSD. It provides smooth playback and recording even if devices are very slow. It’s highly customizable and can be easily extended with additional plugins. Its low CPU & memory consumption saves energy when running on a notebook’s battery.
Play or convert audio files, record new audio tracks from microphone, save songs from Internet radio, and much more! fmedia is free and open-source project, and you can use it as a standalone application or as a library for your own software.

UADE is a music player for UNIX platforms that plays music formats used on the Amiga computer.
Snd is a sound editor modelled loosely after Emacs. It can be customized and extended using either s7 (included in the Snd sources), Ruby, or Forth. Snd is free; the code is available via anonymous FTP as Snd tarball.

ccrma.stanford.edu/software/snd/
ccrma.stanford.edu/software/snd/snd/snd
sourceforge.net/projects/snd
Aften is an audio encoder which generates compressed audio streams based on ATSC A/52 specification. This type of audio is also known as AC-3 or Dolby® Digital and is one of the audio codecs used in DVD-Video content.
Features:
- Converts PCM source audio into AC-3 audio
- Allows for setting of production metadata such as dialogue level, downmix levels, and extended bitstream information
- Supports RAW, WAV, AIFF, and CAFF input file formats
- Supports single multi-channel or multiple mono source files
- Includes several optional pre-processing filters
- Uses multi-threading and assembly optimizations to speed up encoding
ASAP (Another Slight Atari Player) plays and converts 8-bit Atari music (*.sap, *.cmc, *.mpt, *.rmt, *.tmc, …) on modern computers and mobile devices.

asap.sourceforge.net
sourceforge.net/projects/asap
asap.sourceforge.net/web
github.com/epi/asap
Bluemindo is a really simple yet powerful audio player in Python/PyGTK, using Gstreamer. It’s a free (as in freedom) software, released under GPLv3, only.
Bluemindo’s user interface consists of a main view of all your digitized album discs, which is searchable and filterable. The playback mode is gapless and support ReplayGain (it can also automatically choose to switch between Album and Track modes, depending on the kind of music that’s being played). Last but not least, it brings playlist (automatic and user-made), MPRIS/MediaPlayer2 support and lyrics/artwork downloading.

bluemindo.codingteam.net
http://codingteam.net/project/bluemindo
Nootka is an application to help learn classical score notation. It helps in understanding the rules of reading and writing scores and helps with developing skills of playing and singing notes.
Simply: users looks at piece of a score, plays it, while Nootka is listening to it, checks and shows was it played well. All in real time.
Features:
- interactive interface to discover the rules of musical notation
- exercises with possibility to create own sets
- accurate method for detecting sung and played sounds
- natural sound of guitars
- clefs (treble, bass and others) and grand staff
- analysis of results
- different kinds of guitars and their tuning
