Page  571 ï~~BESSIE: A Real Time Interactive Computer Tutorial on Frequency Modulation Synthesis for the NeXT Computer. Anthony G. Holland Associate Professor of Music Skidmore College Saratoga Springs, New York 12866 tholland@pars.skidmore.edu BESSIE is the first real time interactive computer music tutorial for the NeXT computer. Its focus is Frequency Modulation synthesis. BESSIE assumes no prior knowledge of computer music and is intended to be utilized as an aid in teaching the theory and practice of FM synthesis for both neophyte and experienced computer music practitioners. BESSIE carefully leads the student through the basic concepts of FM synthesis and features a brief historical overview of FM along with musical excerpts (Chowning). While the student is not required to move through the tutorial in any particular order, the menu is laid out in such a way as to suggest an orderly progression through the various topics related to FM. ITutorial [~ History 11 ICMC 571

Page  572 ï~~BESSIE controls all FM parameters in real time using various sliders on its main editor window and all parameters may be saved (written to a file) in either Scorefile syntax or as a.snd soundfile. This saving option is of particular value for demonstration and composition purposes. Because BESSIE is able to alter all FM parameters in real time and save those parameters to a file, it functions both as a tutorial and as an FM "voice editor" whose values can be stored "on-line". In April of 1991, BESSIE 1.0 was made available via anonymous FTP as "freeware" at all NeXT music archive locations (pub/next/bessie.tar.z on many archives). This first release focused primarily on simple FM synthesis. BESSIE 2.0 is currently under development at Skidmore College's "DREAMS" (Digital Research in Electro-Acoustic Music) facility and will include a number of important enhancements including a real time line-segment spectrogram display and complex FM. BESSIE requires NeXT system software 2.0. ICMC 572