SoX - Sound eXchange / News: Recent posts

SoX 14.3.0 Released

We are happy to announce the release of SoX 14.3.0.

Source code, Win32 binaries, and Mac OSX binaries can be downloaded from

Release highlights include:

o New filter effects: `sinc', `fir', `biquad'.
o Other new effects: `stats', `overdrive', `vad'.
o New audio device handler for OpenBSD.
o Fixed problems with temporary file on Windows.
o Can now enable automated clipping protection for most effects.
o Automatically `dither' as needed.
o Improvements to AIFF, WAV, FLAC, MP3 handlers.
o ALSA driver now supports 24-bit.
o `spectrogram' effect enhancements including multi-channel support.
o `synth' effect enhancements including new `pluck' type.
o More gain/normalise options.
o Now uses CPU multi-core to speed up some effects.
o SOX_OPTS environment variable for setting default options.
o Interactive playback volume control (on some systems).
o More `soxi' options, including multi-file total duration.
o Can now auto-detect file-type even when inputing from a pipe.... read more

Posted by Chris Bagwell 2009-06-21

SoX 14.2.0 released

We are happy to announce the release of SoX 14.2.0.

You can download source code, win32 binaries, and now Mac OSX binaries from .

Release highlights (see ChangeLog at
for complete list of changes):

Processing chain:
o now supports any number of input files
o now allows multiple effects chains, multiple input pipes and, in some cases, multiple output files
o initial support for Mac OSX audio IO
o better support for large (2G/4G) files.
New effects:
o (ISO 226) loudness control
o RIAA vinyl EQ
o pitch bending
Enhanced effects:
o rate: minimum/intermediate/linear phase, custom bandwidth
o dither: noise shaping
o mcompand: now with Linkwitz-Riley crossover.
Various other small fixes/improvements.... read more

Posted by robs 2008-11-09

SoX 14.0.1 Released

I am happy to announce the release of SoX 14.0.1.

You can download both source code and win32 binaries from

Changes in this release include:

File formats:

o Added support for non-standard, non-WAVE_FORMAT_EXTENSIBLE
(esp. 24-bit) PCM wav (see wavpcm in soxformat.7 for details). (robs)


o Reimplemented reverb to be similar to freeverb. (robs)

Bug fixes:

o Fix Sndtool read error causing noise at start. (Reynir Stefánsson)
o Fix mixer with >4 numbers, and mixer -3 behaving as mixer -4. (robs)
o Fix [1748909] sox does not report remaining playtime of mp3s. (robs)
o Fix failure to read AIFF files with empty MARK chunk. (robs)
o Fix spurious 'Premature EOF' message in some circumstances. (robs)
o Switched to 16-bit for libao driver since not all its plugins
support it (such as oss, nas, and pulse audio) (Morita Sho)
o Stop crash when "rec" is run with no arguments (Morita Sho).
o Fix -V (without argument) on non-gnu systems. (robs)
o Fix reported (with -V) output audio length in some cases. (robs)
o Fix actual FLAC output file audio length in some cases. (robs)
o Fix poor 24-bit FLAC compression & support newer versions of
libFLAC (1.2.x). (robs)
o Fix loss of 1 decoded FLAC block when using "trim 0 ...". (robs)
o Fix trim when first effect with IMA-ADPCM input wav file. (robs)... read more

Posted by Chris Bagwell 2008-01-30

SoX 13.0.0 Released

I am happy to announce the release of SoX 13.0.0.

You can download both source code and win32 binaries from

This is a major release of SoX and we took this occasion to greatly
enhance the command line options and output display of the
program. Please expect some script breakage because of this.

This release contains the largest collection of new features
and bugfixes to date. The SoX project has two new full time
developers, Rob Sykes and Reuben Thomas, to thank for this.
Welcome aboard!... read more

Posted by Chris Bagwell 2007-02-12

SoX 12.18.2 Released

I am happy to announc the release of SoX 12.18.2.

You can download both source code and win32 binaries from

Changelog for this release follows:

* Detect when disk is full
* Internal libst cleanups
* Fix synth effect to write exact amout of samples.
* Fix hackup when writing stereo MP3 files.
* Expanded help screen and command line options.
* Support external GSM libraries.
* Fix crashes in nul file handler.

Posted by Chris Bagwell 2006-09-04

SoX 12.18.1 Released

I am happy to announce the release of SoX 12.18.1.

You can download both source code and win32 binaries from

Changelog for this release follows:

* Several filters were going into infinite loops and created huge files.
* ctrl-c now aborts filters that are in drain mode.
* Stop crash when file type could not be auto detected.
* Allow multiple '.' in input filename.
* Fixed clip bugs in noisered and mcompand.
* Fixed some overflow crashes in AIFF handler.
* Force to binary mode in windows for pipes to work.
* Fixed infinit loop when reading MP3 tags of exact size 8192.
* Fixed typoe in Visual Studio 6 project file.
* Fixed problems in silence effect when removing multiple periods of silence from middle of file.
* Reduced window size of silence effect greatly to prevent leaving in silence.
* Prevent crashes when printing error messages.
* Added support for Open Watcom compiler.
* Fixed a flow() bug that now allows back-to-back reverse effects.
* Added support for muliple channels in .dat files.

Posted by Chris Bagwell 2006-05-07

SoX 12.17.9 Released

I am happy to announce the release of SoX 12.17.9.

You can download both source code and win32 binaries from

Changelog for this release follows:

* Add optional status line that tracks progress of read/write routines.
* Updates to compile under VC6.
* Fix remaining samples when seeking in AIFF, SMP, and WAV handlers.
* Changed noisered to only warn during clipping instead of aborting.
* Fixed bug were audio was lost every buffer read when running both -c and -r options together on mono audio.
* Fix silence effect to allow negative periods to be specified (t o remove silence from middle of file).
* Track length of Ogg Vorbis files on read.
* Converted ALSA driver to use asoundlib instead of directly talking to kernel driver. This means that device names are now the ALSA logical names instead of /dev type names.
* Added ALSA support to play/rec scripts.
* Added st_open*, st_read, st_write, st_seek, and st_close routines to help simplify devloper interface to libst.
* Force word-alignment on AIFF SSND and APPL chunks on input.
* Fixed bug where -4 option didn't work with avg effect.
* Fixed fade's fade-out-length to match man page descriptin.
* Allow aborting SoX with SIGTERM, along with previous SIGINT.

Posted by Chris Bagwell 2005-12-06

SoX 12.17.8 Released

I am pleased to announce the release of SoX 12.17.8. It is avaliable at

This is mostly a bugfix release. Things that have changed since 12.17.7 include:

o noisered effect had compile problems with some compilers.
o "-x" option was being ignored since 12.17.7.
o Stuart Brady added support for reading and writing RIFX files (big endian RIFF/WAV files). Also added support for auto detecting DEC-style ".sd\0" files.
o Gene Mar found typo in polyphase nuttall calculation.
o SMP buffer overflow (detected by gcc 4.0). Reported by Marcus Meissner and Matthias Saou.
o Fixed URL in manpage to resample overviews.
o Fixed WAV handler so that it didn't think WAV chunks with max size were invalid chunks. This allows WAV's to be used in pipes since they have to default to max size.
o WAV files with alaw or ulaw data don't need extended format chunks. (Lars Immisch)
o In AIFF files, fixed problem were short comments should cause AIFF handler to get confused and become misaligned.

Posted by Chris Bagwell 2005-08-22

SoX 12.17.7 Released

I am pleased to announce the release of SoX 12.17.6. It is avaliable at

Things that have changed since 121.7.6 include:

o Christian Weisgerber sent patches to man page fixes
and patches for sunaudio driver on openbsd.
o Default volume for soxmix wrongly set to 0 instead
of 1/#_input_files (float rounding error).
o Update to ALSA driver to do a better job of detecting
unsupported sample rate/size/encoding and change to
a supported one.
o Fix bug in alsa writing were last last partial buffer
wasn't being flushed.
o Guentcho Skordev pointed out ogg vorbis files were using
the same value for serial numbers each time.
o Changed sox to only read the exact size of a WAV data chunk
if cooledit IFF LIST chunk is found at the end of the file.
Normally, this isn't done to allow reading > 2gig WAV files.
o Modified configure to detect cygwin compiler after detecting
gcc compiler (fixes some default CFLAGS options).
o Added explicit rule for compile *.o from *.c so that
CPPFLAGS is always referenced. Not all platform's default
rule includes CPPFLAGS (FreeBSD).
o Under linux, add include path to /lib/modules/* so that ALSA
include files can be auto detected.
o Ian Turner added an effect to remove noise from an audio
file by first profiling silent periods of the audio
to determine what the noise is (like background hiss on cassette tapes).

Posted by Chris Bagwell 2004-12-21

SoX 12.17.6 Released

I'd like to announce the release of SoX 12.17.6. It is avaliable at

Things that have changed since 12.17.5 include:

o Fixed the crash when processing WAV files.
o General cleanup of code (warnings from valgrind, c++ cleanup,
getting ready to allow reading from memory instead of just files, etc).
o Restructure directory layout for easier browsing.
o Modified sox to accept multiple input files. Result is concatenating
audio files together.
o Fixed hangup when reading mp3"s with large ID3v2 tags.
o Volume option (-v) now tracks file its specified with. This is
important for multiple input files. Specify with output filename
for an overall volume adjustment or with input filename for
fine tuning each file.
o soxmix increased from 2 input files to upto 32 input files.
Also, defaults to modifying audio volume of each file by
1/#_input_files which can be overridden with -v option on each
input file.
o Added a scripts directory with samples of working with sox.
For example, will take two audio files and perform
a crossfade between end of 1st and beginning of 2nd file.
o Trim effect will do a seek() call when possible to greatly
speed up processing time.
o Added a new multi-band compander.
o Modified silence effect to allow removing silence from middle of file.
o Added support for float data in .au and .wav files.
o Modified sox to only work with normalized floats (-1:1).
o Various bugfixes related to clipping.

Posted by Chris Bagwell 2004-10-14

SoX 12.17.5 released

I'd like to announce the release of SoX 12.17.5. It is avaliable from

The following things have changes since SoX 12.17.4:

o Thomas Klausner sent in patches to compile audio drivers under
o Rahul Powar pointed out a memory leak in the WAV file handler.
It wasn't calling the correct close() function when closing
input files.
o Modified play.1 man page to not use multiple name lines. This
appears to confuse some conversion programs. Updated sox.1
man page for typo in reverb option.
o Andrew Church fixed problem with header of stereo 8SVX files.
o Jimen Ching added support to scan over garbage data at the
beginning of MP3 files to find valid frames. This is useful
to play WAV and AIFF files that have MP3 data in them until
those handlers support it directly. To play those, force
sox to use the mp3 handler with the "-t mp3" option.
o Added patch from Ulf Harnhammar to wav handler to prevent
buffer overflows.
o Added patch from Redhat to allow resample to work on certain 64-bit
machines (Sam Varshavchik)
o Tony Seebregts added a file handler for headerless Dialogic/OKI ADPCM
files (VOX files).
o Jan Paul Schmidt added a repeat effect to do loops the brute force way.
This is also good for file format that don't support loops as well.
o Fix for OSS driver in rate tolerance calcs that were off because
of type conversion problems. Guenter Geiger.
o Allow reading sphere files with headers greater then 256 bytes. Jimen
o Fix for vorbis were comments are displayed in KEY=value format always.
Stop printing some info to stdout in case output is a pipe. Guenter
o J Robert Ray submitted fix for AIFF handler to ignore lowercase
chunks that are unknown.
o Bugfix for 8-bit voc files. Jimen Ching
o General warning cleanups (cbagwell)
o Memory leaks in reading WAV files (Ufuk Kayserilioglu)
o Rearrange link order of ogg vorbis libraries so that they
can be compiled as static. (Christian Weisgerbr)

Posted by Chris Bagwell 2004-08-15

SoX 12.17.4 released

SoX is meant to be the Swiss Army Knife of sound processing utils. It can convert audio files to other popular audio file types and also apply sound effects and filters during the conversion. This release adds support for reading and writing MP3 files using the external libraries libmad and libmp3lame; and a number of bugfixes.

I'd like to announce the release of SoX 12.17.4. It is avaliable from read more

Posted by Chris Bagwell 2003-03-24

SoX 12.17.3 Released

SoX is meant to be the Swiss Army Knife of sound processing utils. It can convert audio files to other popular audio file types and also apply sound effects and filters during the conversion.

I'd like to announce the release of SoX 12.17.3. It is available for download from

The following items have changed since the release of SoX 12.17.3:

* Bugfix to Pan effect to work when input and output files have
different number of channels.
* Many bugfixes to trim effect.
* Options parse bug fixed in fade effect.
* IMA support wasnt compiling on alph's.
* Fixed length and encoding error for 16-bit VOC files.
* Moved to a config.h style configuration header instead of passing
options via compiler command line.
* Lots of bugfixes to Silence effect. Now also uses RMS values to
help ignore pops.
* Fixed install problem with play script when installing from
somewhere else then the src directory.
* Now include GSM library inside of the sox package. No need for
external library anymore.
* Modified raw write routines to use a new faster method similar to
read update in 12.17.2.
* Added support for A-law and u-law files that have their bit-order
inversed (ie. MSB becomes LSB).
* Added flush after parameter changes to most audio players to
prevent noise.
* Auto detection was failing for files less then 132 bytes.
* Internal private data wasn't using 8-byte alignment and causing
crashes on Sparc and Motorola CPU's.
* Major internal cleanups to work better on 32-bit platforms.
* There were a few cases where SoX thought EOF was an error
condition and it wasn't.
* Change "float" to be an encoding type of data. Need to specify a
size of 32-bit or 64-bit on command line to represent "float" and
* Change default to use Fast u-law/A-law lookup tables.
* Several bugfixes to A-law/u-law support. Previously it was quite
easy to clip audio data when working with A-law data.
* Reading Ogg Vorbis files would sometimes not detect EOF properly.
* Added A-law and u-law read support to VOC handler.... read more

Posted by Chris Bagwell 2001-12-19

SoX 12.17.2 Released

I've released version 12.17.2 of SoX. Its almost a year in the making and contains tons of bugfixes and a few new effects.

Hightlights include:

o Bugfix to Polyphase effect (no longer makes files longer then they should be)
o New syth effect to create signals (see script for examples)
o New silence effect for triming off silence from files
o Now attempts to look at audio data to detect input format instead of just extension
o New Ogg Vorbis file handler (if you have external library installed)
o Avg effect can handle any combination of input/output channels
o trim and fade effects calculate time values correctly
o Ctrl-C stops recording again
o New experimental soxmix program to mix two sound files into one
o Bugfix in lowp filter
o AIFF files can read non-standard size data (ie 12-bit).... read more

Posted by Chris Bagwell 2001-09-17

SoX 12.17.1 Released

This release is mainly a bugfix release. Please see the SoX web page fore more information.

Posted by Chris Bagwell 2000-11-21

SoX 12.17 Released

Version 12.17 of SoX has been released. It contains lots of new effects and filters as well as improvements to the quality and performance of older features.

Check out the SoX home page for a sumary of changes.

Posted by Chris Bagwell 2000-09-12

SoX project moves to Sourceforge

The SoX project has finally moved over to Sourceforge to benefit from all of its resources.

Posted by Chris Bagwell 2000-09-05