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Calf Studio Gear - Audio Plugin Pack / News: Recent posts

Calf 0.0.60

Just in time for Linux Audio Conference 2015, we are presenting the new
release of Calf. This release features:

  • a large number of new plugins from the Calf Team members and some new
  • technology updates to reflect the evolution of the LV2 plugin
  • many improvements, both in terms of user interface and the plugin
  • bug fixes for the framework and the plugins... read more
Posted by Krzysztof Foltman 2015-03-29 Labels: 0.0.60 release

Calf 0.0.19 released

This version of Calf includes several major additions and enhancements, mostly thanks to the new team members, Markus Schmidt and Christian Holschuh. There are too many changes to mention, but the most important are:

  • new GUI theme, to make Calf more usable and aesthetically pleasing
  • several mastering-oriented plug-ins:
    • equalizers of varying complexity
    • a large number of dynamics-oriented plugins - compressors, limiters and gates - simple, sidechain and multiband
    • distortion-like plugins: exciter, saturator and bass enhancer (using work of Tom Szilagyi)
    • powerful multi-function analyzer to produce spectrograms, phase correlation diagrams and plain old spectrum analysis graphs
    • tools for working with mono vs stereo signals
  • other plugins: de-esser, pulsator (a tremolo/autopanner plug-in), a simple wrapper for Fluidsynth soundfont player
  • various enhancements for Monosynth and Organ synthesizers
  • improved and simplified internal architecture
  • improved support for LV2 plug-in standard... read more
Posted by Krzysztof Foltman 2012-10-21

Calf released

This version is a bug-fix release. A major bug regarding compatibility with Rosegarden has been corrected. Also, the Rotary Speaker plugin uses a correct class name (SimulatorPlugin).

Posted by Krzysztof Foltman 2010-08-22

Calf 0.0.17 released

This is the first release from the New(tm) Improved(tm) two-person Calf development team.

First of all, it contains one new plugin, Compressor, which has been created by the new member, Thor Harald Johansen. The new plugin is intended to provide quality and ease of use comparable to a professional compressor.

There are also major improvements in graphical interfaces of most of the plugins. The new interfaces use custom layouts, and some plugins have additional graphical displays to assist in parameter adjustments.... read more

Posted by Krzysztof Foltman 2008-11-28

Calf released

Version has been released. No radical changes in core functionality this time. One new effect has been added, a multi-tap stereo chorus plugin, quite predictably called MultiChorus.

However, this release can potentially be interesting to hard-core users of LV2-based modular synthesizers (particularly a modular synthesizer Ingen created by Dave Robillard), as it contains a completely new set of about 60 small LV2 plugins. Those plugins cover areas like logic gates, flip-flops, multiplexers, counters, arithmetic operators, basic oscillators and filters (1st and 2nd order) and similar "discrete" modules. They are of limited usefulness for now, so they are disabled by default. Use --enable-experimental configure option to enable them. For more information about Ingen, see http://drobilla.net/software/ingen/... read more

Posted by Krzysztof Foltman 2008-10-29

Calf repository moved to Git

As an experiment, I've decided to migrate the source code repository to use Git distributed version control system instead of previously used Subversion.

The source code is now available at the following address:


To get Calf from repository, use:

git clone git://repo.or.cz/calf.git calf

To update to the newest version, use:

git pull

The web interface for browsing changes in the repository is available at:... read more

Posted by Krzysztof Foltman 2008-10-28

Calf 0.0.15 released

Version 0.0.15 has just been released. This release contains another set of improvements in existing plugins and the DSP and GUI libraries they are built on.

The organ synthesizer is now equipped with a new, frequency modulation-based percussive section, with editable modulation keytrack curve (DSSI and JACK host only). The new percussive section has a polyphonic mode as well as 3 "old" monophonic modes. New presets have been added. UI controls have been rearranged to fit in lower screen resolution.... read more

Posted by Krzysztof Foltman 2008-08-19

Calf 0.0.14 released

Calf version 0.0.14 has been released today. No major changes, just small fixes and minor improvements here and there.

Stability is improved, Calf Organ and Monosynth should consume less memory and start faster. Knobs have been improved (including new "endless" subtype). New preset handling makes upgrades easier. There are also 4 new built-in Monosynth presets.

This is (hopefully) the last version with small incremental improvements only. The next version (to be released in October) will likely contain major updates and a new plugin, but it will not be released until September or October.

Posted by Krzysztof Foltman 2008-07-05

Calf 0.0.12 released

This release brings many new features developed over last 4 months - new JACK host and Phaser plugin, redesigned Organ plugin, experimental LV2 support and lots of other changes. It also removes a dependency on libphat.

The new JACK host is capable of adding more plugins to the running instance, and features a main dashboard window with VU meters and MIDI activity indicator (where applicable).

The Phaser is a stereo effect based on series (up to 12) of 1st order allpass filters with global feedback.... read more

Posted by Krzysztof Foltman 2008-05-28

Calf 0.0.10 released

Winter holidays are over, and 0.0.10 is available. This release adds the GUI to the DSSI plugins, mouse wheel support in non-PHAT knobs and more features as well as bugfixes in Reverb.

For those who also missed the unannounced 0.0.9 - be sure to download this release. It also includes numerous additions and improvements in Monosynth, new knobs and dynamically updated filter graph, improved JACK host and denormal fixes everywhere.

Posted by Krzysztof Foltman 2008-01-06

Calf 0.0.8 released

This version contains significant improvements and fixes for Monosynth, both the synth itself and the DSSI and JACK wrappers.

Preset handling is improved, and provided are some "factory" presets for Monosynth.

Have fun trying it out, and of course, please report any bugs you find.

Posted by Krzysztof Foltman 2007-12-23

Calf 0.0.6 released

The new version contains an "official" release of Monosynth (with several last-minute improvements like portamento and better envelope), as well as various bugfixes.

Calf currently supports LADSPA (effects only), JACK (0.103.0 or newer) and DSSI. It supports DSSI for effects as well, so the initial parameter values may be more reasonable.

Happy testing!

Posted by Krzysztof Foltman 2007-12-15

Experimental DSSI support

Current SVN version contains two new instruments - organ synth (poor-man's emulation of one manual of B3 organ and rotary speaker) and monosynth (a simple but capable monophonic virtual analogue synthesizer).

Both instruments have a JACK host version (calfjackhost) and a simple DSSI version (tested successfully with jack-dssi-host).

That instruments are currently fully functional, but there's plenty of room for improvement - it's just a question of deciding which features are more desirable. I'm open to suggestions.... read more

Posted by Krzysztof Foltman 2007-12-14

First release

First pre-alpha version of Calf has been released. It contains three plugins - a simple 12dB lowpass/highpass resonant filter, a flanger and a reverb, in two versions - as LADSPA plugin and as a standalone JACK client application, with a simple GUI using GTK+ and PHAT library.

They have been optimized for audio quality, not speed, and I hope to speed up the implementation considerably in future. I also plan to add support for more plugin interfaces and improve existing support for LADSPA and JACK.... read more

Posted by Krzysztof Foltman 2007-11-30