Hydrogen is an open-source drum machine created by Alessandro Cominu, an Italian programmer who goes by the pseudonym Comix. Its main goal is to provide professional yet simple and intuitive pattern-based drum programming.
Hydrogen was originally developed for Linux, and later ported to Mac OS X and Windows. The graphical user interface for the application uses Qt library, and all code is released under GPL-2.0-or-later.
Features
These are some of the features of Hydrogen:
Pattern-based sequencer, with unlimited number of patterns and ability to chain patterns into a song.
192 ticks per whole note with individual level per event and variable pattern length.
Unlimited instrument tracks with volume, mute, solo, pan capabilities.
Multi-layer support for instruments (up to 16 samples for each instrument).
Sample editor with basic cut and loop functions.
Time-stretch and pitch functions.
Time-line with variable tempo.
Single and stacked pattern mode.
Ability to import/export song files.
Support for LADSPA effects.
Real-time slide control for swing.
Option to slightly randomize velocity, time, pitch and swing functions to give a more "human" playback.
Multiple patterns playing at once.
Various drumkits available to download (Rock, Jazz, Electric, Percussions...), plus support to create a custom drumkit.