Gcomp is an interactive software based on a graphical approach, developed at the Queem’s University, Ontario. It was designed for processing and mixing sound files generated by Cmusic or recorded through digital equipment.
Premises – The Queen University of Kingston, Ontario in Canada, in the eighties has oriented its activities, compared to the problems of computer music, towards the development of tools dedicated to the musical composition in the perspective of concrete music. Having equipped the computer section of the Department of Music with the software Cmusic it is the first witness. Specifically, in the early eighties, it was decided to develop utilities and software, which allows for the manipulation and mixing of sounds generated by a WAX 11/750 computer and Cmusic or digitally recorded and stored in a memory of 300 Megabytes.
Waves – Two were the software that, in the eighties, you could consider the most important tools for processing and mixing of digital signals in use at Queen’s University: Waves and Gcomp. The first is a simple audio editor very similar, in function and structure, to the program S by James Moorer or Edsnd.
Gcomp – More like NROFF, the text editor developed for Unix, is Gcomp. This is an interactive software that allows you to edit graphically the control functions for creating and mixing sound material, a process, this latter, that could also be automated. In a first phase was developed to work in association with the Music 11; later was developed a version written in C that can work in conjunction with Cmusic. The output generated by Gcomp consisted of a stream of data stored on disk to be subjected to conversion for the final hearing.
To avoid confusion in the workplace, Gcomp was structured by providing a separation between processing operations and mixing of sounds. A third mode of operation, however, has been introduced to provide an editor of features, less specific, which could be used exclusively for Gcomp or even to generate functions to be used directly with Cmusic. Each of these three modes, defined function-definition mode, process mode and mix mode, could be invoked by typing a single key.
Advantages and disadvantages – One of the positive aspects of Gcomp was undoubtedly its portability. The first version, developed for the Music 11 (for which generated notes lists and instrument codes), was limited to software too specific. The C version, on the other hand, guaranteed use with all those programs that, just since the eighties, began to develop with the new programming language. Among its limitations, however, the inability to use Gcomp in real-time; though it was a software failure common to many of those years.
Other utilities – In addition to Gcomp were also made routines written in C, can pick up data from Gcomp to generate stereo audio signals. These routines, some of which are adapted from Cmusic and the CARL System, were made by Greg Hermanovic and were part of the software SPAM (Signal Processing And Mixing). At Queen’s Univeristy was prepared also a version of SPAM for DEC VAX computers, capable of interfacing with Cmusic.
For this topic I’ve read:
 Colin Banger, Bruce Pennycook, Gcomp: Graphic Control of Mixing and Processing, Computer Music Journal, Vol. 7 , 1983.