This is a free software version of SGI's audiofile library. It provides a uniform programming interface for processing of audio data to and from audio files of many common formats.

Currently supported file formats include AIFF/AIFF-C, WAVE, and NeXT/Sun .snd/.au, BICS, and raw data. Supported compression formats are currently G.711 mu-law and A-law.

SuperCollider is a synthesis engine (scsynth or supernova) and programming language (sclang). It can be used for experimenting with sound synthesis and algorithmic composition.

SuperCollider requires jackd to be installed in your user profile and your user must be allowed to access the realtime features of the kernel. Search for "realtime" in the index of the Guix manual to learn how to achieve this using Guix System.

libsoundio is a C library providing audio input and output. The API is suitable for real-time software such as digital audio workstations as well as consumer software such as music players.

AlsaModularSynth is a digital implementation of a classical analog modular synthesizer system. It uses virtual control voltages to control the parameters of the modules. The control voltages which control the frequency e.g. of the VCO (Voltage Controlled Oscillator) and VCF (Voltage Controlled Filter) modules follow the convention of 1V / Octave.

ALURE is a utility library to help manage common tasks with OpenAL applications. This includes device enumeration and initialization, file loading, and streaming.

Swh-plugins-lv2 is a collection of audio plugins in LV2 format. Plugin classes include: dynamics (compressor, limiter), time (delay, chorus, flanger), ringmodulator, distortion, filters, pitchshift, oscillators, emulation (valve, tape), bit fiddling (decimator, pointer-cast), etc.

libaudec is a wrapper library over ffmpeg, sndfile and libsamplerate for reading and resampling audio files, based on Robin Gareus' audio_decoder code.

aubio is a tool designed for the extraction of annotations from audio signals. Its features include segmenting a sound file before each of its attacks, performing pitch detection, tapping the beat and producing MIDI streams from live audio.

Zita-alsa-pcmi is a C++ wrapper around the ALSA API. It provides easy access to ALSA PCM devices, taking care of the many functions required to open, initialise and use a hw: device in mmap mode, and providing floating point audio data.

FreePats is a project to create a free (as in free software) collection of digital instruments for music production. This sound bank is a partial release of the General MIDI sound set.

python-resampy implements the band-limited sinc interpolation method for sampling rate conversion as described by Julius O. Smith at the Digital Audio Resampling Home Page.

This package provides Steve Harris's LADSPA plugins.

This package provides a LADSPA plugin for a four-band parametric equalizer. Each section has an active/bypass switch, frequency, bandwidth and gain controls. There is also a global bypass switch and gain control.

The 2nd order resonant filters are implemented using a Mitra-Regalia style lattice filter, which is stable even while parameters are being changed.

All switches and controls are internally smoothed, so they can be used live without any clicks or zipper noises. This makes this plugin suitable for use in systems that allow automation of plugin control ports, such as Ardour, or for stage use.

Faust is a programming language for realtime audio signal processing.

VO-AACENC is the VisualOn implementation of Advanced Audio Coding (AAC) encoder.

This package provides a LADSPA plugin to manipulate the stereo width of audio signals.

SBSMS (Subband Sinusoidal Modeling Synthesis) is software for time stretching and pitch scaling of audio. This package contains the library.

Cubeb is Mozilla's cross-platform audio library.

Noise Repellent is an LV2 plugin to reduce noise. It has the following features:

1. Spectral gating and spectral subtraction suppression rule

2. Adaptive and manual noise thresholds estimation

3. Adjustable noise floor

4. Adjustable offset of thresholds to perform over-subtraction

5. Time smoothing and a masking estimation to reduce artifacts

6. Basic onset detector to avoid transients suppression

7. Whitening of the noise floor to mask artifacts and to recover higher frequencies

8. Option to listen to the residual signal

9. Soft bypass

10. Noise profile saved with the session

LADSPA is a standard that allows software audio processors and effects to be plugged into a wide range of audio synthesis and recording packages.

The Odio SACD shared library is a decoding engine which takes a Super Audio CD source and extracts a 24-bit high resolution WAV file. It handles both DST and DSD streams.

alsa-midi-latency-test measures the roundtrip time of a MIDI message in the alsa subsystem of the Linux kernel using a high precision timer. It calculates the worst case roundtrip time of all sent MIDI messages and displays a histogram of the roundtrip time jitter.

The LV2 Toolkit (LVTK) contains libraries that wrap the LV2 C API and extensions into easy to use C++ classes. It is the successor of lv2-c++-tools.

Rakarrack is a richly featured multi-effects processor emulating a guitar effects pedalboard. Effects include compressor, expander, noise gate, equalizers, exciter, flangers, chorus, various delay and reverb effects, distortion modules and many more. Most of the effects engine is built from modules found in the excellent software synthesizer ZynAddSubFX. Presets and user interface are optimized for guitar, but Rakarrack processes signals in stereo while it does not apply internal band-limiting filtering, and thus is well suited to all musical instruments and vocals.