File Extension GP3
File extension GP3 is most commonly associated with a Guitar Pro Version 3 file, which contains musical scores and tablature for use with guitar, bass and banjo instruments. The GP3 file extension is also used to denote a compressed graphic using the Group 3 file format, which was originally designed purely for fax transmission.
Guitar Pro is a fully-featured tablature editor which is used to produce and edit musical scores for stringed instruments such as guitar and bass. The default file format produced by Guitar Pro is GP3, which includes support for multiple tracks with MIDI playback. GP3 files can be edited using Guitar Pro, or exported as File extension MIDI tracks or ASCII text, allowing musical scores to be shared amongst players. GP3 files are commonly found on the Internet on tablature websites, which offer user submitted interpretations of musical scores for download for educational purposes. These can then be loaded using Guitar Pro and played back or modified as required. Often, GP3 files contain multiple instrument tracks, and are used as backing tracks through the omission of one or more of the instruments.
A similar file format to GP3 is PTB, which is the default file format of Power Tab, an alternative albeit less fully featured tablature authoring application. Both GP3 and File extension PTB formats support multiple instrument tracks as well as the use of standard tablature notation for stringed-instrument techniques such as hammer-on and vibrato, which significantly simplifies musical scores.
GP3 is a proprietary format which can only be opened and edited using an appropriate version of Guitar Pro. Though GP3 files store music as tablature, they also contain additional track and instrument data, and so contain no useful information if opened with a text editor. GP3 files which relate to fax images can be opened using a compatible fax viewer such as FaxSee Pro or Smart FaxSee.