Glossary

Algorithm, algorithmic

An algorithm is a perpetuated set of calculations designed to achieve a specific goal. It is the mathematical form of a machine and thus the ancestor of all Artificial Intelligence.

General MIDI (GM)

An industry standard for sound devices, arbitrarily defining the musical instruments ("programs"), channels and effects that are available: Program #1 has to be a piano, program #72 a clarinet etc. There are 16 channels, whereas channel 10 is reserved for drums and percussion. The two biggest MIDI device manufacturers Roland and Yamaha defined their own proprietary standards called GS (Roland) and XG (Yamaha). The new General MIDI 2 GM2 standard included the enlarged specifications of these rivaling solutions.

Microtonality, microtonal

In classical Western music, the octave is divided in 12 equal parts (12 tone equal temperament or 12TET). In other music cultures, e. g. in the Arabic world, there are different divisions. A lot of this tunings are using scales with other intervals than the usual semitone, e. g. quartertones. These tunings are called microtonal.

Musical Instrument Digital Interface (MIDI)

An industry standard protocol defining how data are exchanged between certain music-related hard- or software (e. g. sound cards, synthesizers, sequencer software). There are only two possible roles in a MIDI network: master and slave. While in slave mode, the device has to obey the master's orders. In other words: the master device is a remote control for the slave device.

Standard MIDI File (SMF)

A thread of control data specified for a compatible sound device. Can be compared to a paper roll for a player piano or a score. A SMF doesn't contain music, but instructions to trigger a sound device ("First play Note C, then D, then E" etc.). Therefore, a SMF is normally much smaller than an audio file (50 KB is BIG!). There are three types of MIDI data: Note On/Offs, Controllers, and System Exclusive (SysEx) data. Note On/Offs trigger the sounds. Controllers are managing common parameters like volume, panorama position, pitch, timbre etc. SysEx data transmit device-specific informations like selecting a specific sound sample, inserting an effect etc. As the name suggests, they exclusively work with the sound device they were designed for (e. g. the Edirol StudioCanvas SD-80 MIDI Sound Module).

Virtual Instrument (VI)

A software that simulates the sounds of a real instrument on a computer. Can be run as a plug-in hosted by a sequencer (e. g. Cubase, Logic) or as a standalone application (e.g. Vienna Ensemble). A Standard MIDI File triggers the VI's pre-recorded tones, loops, and phrases that were performed by real musicians. These recordings are organised in a sample library, which can be accessed in realtime by the VI. The better the library, the more it enables the user to desktop-arrange his/her composition so that the result can no longer be distinguished from a recording with real instruments. At least that is what manufacturers of VIs are after ;-)