Music IV is a sound synthesis software for computer music. In chronological order is the fourth Music N programming language. Less obvious features, than its predecessor Music III, but equally important for the subsequent development of computer music.
Background history – The Music IV is the result of collaboration between Max Mathews and Joan Miller. The new software was completed in 1963. In programming terms, Music IV presents news less substantial than the Music III. Mathews himself has highlighted the fact that the Music IV introduced novelty computing facilities, rather than new music features:
Music IV was simply a response to a change in the language and the computer. It Had some technical advantages from a computer programming standpoint. It made heavy use of a macro assembly program Which Existed at the time
With the adoption of macro, tried to speed up the use of the software. There is another aspect to note respect to computer programming standpoint: the Bell Labs researchers did not stop to use the original IBM 7094 assembly language but developed a modified version. This meant that the Music IV could not in any way to work on other IBM 7094, but only on the machine of Bell Labs. Finally, among the new features, we also recall the introduction of a new digital filter.
Beyond the Bell Labs – Paradoxically, although the Music III had the advantage of being a program that is already widely known, tested and reliable, and although the Music IV was less portable, researchers from other centers of research, looked at this last more interested, rather than the previous software. The adoption of macro made using software fairly fast, and this was perceived as a matter of great interest. The success of the Music IV is demonstrated by the new software, developed elsewhere, which in one way or another was heavily influenced by the program of Max Mathews. This is the case of the Princeton Music IVB and Music IVBF, or the Argonne Laboratories Music IVF. From this moment, then, research on music software ceases to be an activity confined to Bell Labs and is inserted, gradually, in a broader international context that will bring the Music N outside of the United States.
The graphical approach – In reality, at the two new features previously introduced, there is another that comes a few years away from completion of Music IV, even years after its distribution. Speaking of the general characteristics of the Music N, said of their alphanumeric approach. With the Music IV, Mathews has decided to develop software that would allow a graphical approach, limited to the section of the score: he and his associates developed the Graphic 1. Beyond its success, probably indifferent as in the following Music V was not reproposed, the Graphic 1 acts as a strong element of innovation that will find applications also in the subsequent generations of software. The success of most software today is linked to the use of graphic approaches: intuitive interfaces that speed up the use of the software itself. Certainly the Graphic 1 highlighted certain difficulties and weaknesses related to the Music N characteristic alphanumeric approach.
Here, you can read the Programmer’s manual written by Mathews and Miller:
For this topic I’ve read.
 Curtis Roads, Interview with Max Mathews, Computer Music Journal, Vol. 4 , 1980.
 Max Mathews, Graphical Language for the Scores of Computer-Generated Sounds, Perspective of New Music, Vol. 6 No. 2, 1968, pp. 92 – 118.