Siepura is a free polyphonic multitimbral software synthesizer for GNU/Linux. It has 3 saw/square oscillators with hard sync, a noise generator, 2 ring modulators that can be swapped for FM modulators on oscillator 3, 2 LFOs capable of oscillating at audio rates, 3 ADSR envelopes, a resonant filter and a comprehensive modulation matrix. It uses ALSA for input and output and has a GTK+ user interface.

Siepura is in an early stage of development. It may not work at all or it may crash any time (even though it certainly shouldn't crash and it hasn't done that for me - yet). It consumes an enormous amount of CPU power. Please take a look at TODO for a list of known problems and limitations in the current version.

It may lose your presets or other data. The author takes no responsibility of such losses. Some sounds do not yet sound the way they should yet so your presets may sound different in future versions. The sounds saved with this version may not load properly with the next version due to changes in file format.

In other words: at this point Siepura is not much more than a toy. You have been warned. However, you are free to report any bugs you find. Future versions will contain improvements but no release schedule whatsoever is currently set.


Siepura is written in C for the GNOME 2.6 application platform. Siepura requires gtk-2.0 >= 2.4, libxml-2.0 >= 2.4.16, libglade-2.0 >= 2.4.2, GConf >= 2.0, ALSA >= 0.9.0 and their dependencies.

Command Line Options

  -D, --device=NAME        Select PCM by name
  -b, --buffer-size=#      Buffer duration is # frames
  -p, --period-size=#      Distance between interrupts is # frames

If Siepura does not start with the default settings ("default" ALSA PCM, buffer size 4096, period size 1024) you can use these options to set the output settings so that Siepura works. Siepura will store the settings in GConf so you don't have to specify them again. The settings specified on the command line override the values found from GConf so if your settings won't work you can use these options to reset them. It is highly recommended to set buffer size to 1024 and period size to 128 if your sound card supports such sizes.


Siepura is currently only available from the Savannah CVS repository. Take a look at the Savannah CVS page for Siepura for details.


Please report bugs and send suggestions using the Savannah bugs page for Siepura.


Siepura is programmed by Vesa Halttunen <>.

© 2005 Vesa Halttunen.