Some people say that they haven't switched yet to a free operating system because they need a sequencer software for composing music with their computers. So LMMS, which is a free sequencer, could be a trump card in the ongoing battle for the desktop.
A song arranged in LMMS
LMMS consists of several windows. The song editor is the heart of the program, where you arrange the various parts of your composition along the time axis. Instruments, samples and synthesizer sounds are shown in different tracks.
Most tracks are composed in the beat and bassline editor. Drum parts are entered just by specifying when a drum sound shall be triggered. For other instruments or synthesizer tracks you can use a piano roll and enter the desired notes. If you insert a bassline into your composition in the song editor the bassline will loop if necessary. If you want to enter the notes using a real instrument you can use the MIDI interface. It is possible to enter notes directly into the song editor as well, for example for your fifteen minute guitar solo.
The piano roll
Editing tracks using the piano roll is pretty straightforward. The piano roll presents a track in a pitch over time display. Notes can be inserted by clicking on the desired pitch at the desired time. The note value can be changed by simply resizing it with the mouse. The volume of each note can be adjusted as well. Unfortunately, LMMS offers no undo function, neither in the piano roll nor anywhere else.
The actual sound of an instrument is determined by its sample. This is an OGG or WAV file of a real instrument (or something completely different). LMMS automatically transposes the sample to result in the desired pitch, so one sample can cover a range of multiple octaves. This is a great thing because new instruments can be added easily and you can even build something bizarre and fun like a chainsaw playing different notes. The number and variety of samples included with LMMS are quite impressive, too.
LMMS comes with four different software synthesizers. One simply allows the manipulation of a sample by adding filters, low frequency oscillations and the like. The BitInvader plugin is a wavetable synthesizer, which means that you directly create the waveform for your sound. A simple guitar synth and a synth consisting of three oscillators complete the plugin list. Not all options are documented, however if you have experience with synthesizers you probably know what to do. Most controls offer a basic explanation by right-clicking on them and selecting "Help".
While the rich feature list for synthesizers makes LMMS most suitable for electronic music there is no real obstacle to use it for other styles as well. The demo songs included with LMMS provide an insight on what is possible.
If you feel your composition is complete you can export it to an OGG or WAV file. It is good to see that the LMMS developers chose to not implement the ubiquitous MP3 format in order to prevent to threaten the freedom of the project by patent claims. Importing MIDI files is also supported.
While there is no scripting available in LMMS, you can either use scripts to generate a MIDI input or edit the LMMS project files, which are stored in an XML format.
LMMS is definitely going into the right direction. While it may not convince every user of a proprietary system, you should have a look at it if you are interested in composing music on your computer.