The basic component of an instrument. An instrument is defined by one or more regions.

Inside the definition file, a region starts with the ‹region› header. A region is defined between two ‹region› headers, or between a ‹region› header and a ‹group› header, or between a ‹region› header and the end of the file.

Following the ‹region› header one or more opcodes can be defined. The opcodes are special keywords which instruct the player on what, when and how to play a sample.

Opcodes within a region can appear in any order, and they have to be separated by one or more spaces or tabulation controls. Opcodes can appear in separated lines within a region.

Opcodes and assigned opcode values are separated by the equal to sign (=), without spaces between the opcode and the sign. For instance:


are valid examples, while:

sample = cello_a4_pp.wav

Is not (note the spaces at the sides of the = sign). Input Controls and Performance Parameters opcodes are optional, so they might not be present in the definition file. An 'expectable' default value for each parameter is pre-defined, and will be used if there's no definition.

Example region definitions:

<region> sample=440.wav

This region definition instructs the player to play the sample file '440.wav' for the whole keyboard range.

<region> lokey=64 hikey=67 sample=440.wav

This region features a very basic set of input parameters (lokey and hikey, which represent the low and high MIDI notes in the keyboard), and the sample definition. This instructs the player to play the sample '440.wav', if a key in the 64-67 range is played.

It is very important to note that all Input Controls defined in a region act using the AND boolean operator. Consequently, all conditions must be matched for the region to play. For instance:

<region> lokey=64 hikey=67 lovel=0 hivel=34 locc1=0 hicc1=40 sample=440.wav

This region definition instructs the player to play the sample '440.wav' if there is an incoming note event in the 64-67 range AND the note has a velocity in the 0~34 range AND last modulation wheel (cc1) message was in the 0-40 range.