Most of my work has been the area of sound analysis/synthesis of musical instrument sounds, and this has resulted in completed preliminary studies on percussion and trombone sounds. In addition, I have developed Music 4C further and will soon release version 1.5 to the outside world. A new spectral dynamic synthesis flute instrument is partially complete. The big news is that I've received a Research Board grant for analysis work which provided a research assistantship and a Power Macintosh computer housed in CMP.
Last Fall I completed a study of the analysis of some percussion sounds, namely the sounds of a chime, a timpani, and a cymbal taken from the McGill University Master Samples compact disk. I presented this work at a meeting of the Acoustical Society of America in November, 1995 (Computer modal analysis of percussion sounds: A preliminary study). Whereas the chime sound consists of widely-spaced partials with frequencies roughly proportional to the series 9,25, 49, =2E... (i.e., (2m + 1)2 for m =3D 1, 2, 3, ...), the frequencies of the timpani and the cymbal are much more dense. However, the timpani is tuned to bring out harmonic partials, which becomes evident after the sound's first several milliseconds, where the timpani's spectrum is very rich. Very soon only harmonic partials (except for the first) are left, rendering the tone a distinct pitch. On the other hand, with the cymbal, the partials retain their density and their inharmonicity throughout the sound. An examination of the cymbal's time-varying spectrum reveals that individual frequencies experience wild amplitude undulations. These conclusions were made evident by plotting 2D and 3D spectrograms for the sounds and by resynthesizing the sounds stretched by a factor of 10. The graphs and analysis/synthesis were accomplished by our program package SNDAN.
In January, Timothy Madden began work as a research assistant with me on some Projects in Musical Sound Analysis, sponsored by the UIUC Campus Research Board. Tim's first assignment was to expand the visualization possibilities of the SNDAN package by implementing gray scale and color in graphics and to use these in the monan commands ftc (2D spectrogram) and pp (3D spectrogram). In addition, the 3D graphs were to include the possibilities for specifying any angle of view, to allow true perspective, and to provide automatic hidden line removal. These changes are virtually complete, and this summer Tim will be moving on to other aspects of the project. One initial conclusion is that the new 3D spectrograms make it much easier to visualize the complex spectra of percussion instruments. In addition, the grant provided funds for purchase of a new Power Macintosh 7500 computer, which is now installed in the Computer Music Project. We expect to be soon installing software on that machine to further enhance our visualization of complex spectra.
Over the Spring Break I took part in a seminar series on Music Signal Processing at the University of Michigan-Ann Arbor hosted by Greg Wakefield and Mary Simoni. My talk was entitled Tools and Applications of Musical Sound Analysis/Synthesis. While there I interacted with Greg Wakefield and two of his students, Rowena Guevera and Andrew Sterian, who are doing work in musical sound analysis/synthesis. Wakefield and Simoni have initiated an interdisplinary project between the School of Music and the Deptartments of EE and CS at the University of Michigan which will soon be housed at their new Media Union on their North Campus. They have received three years of funding and this spring this provided funds to bring in nine seminar speakers.
In May I presented a talk on Inference of nonlinear effects from spectral measurements of wind instrument sounds. The primary thrust of this talk was a series of measurements showing that the mouthpiece-to-bell output filter function is in fact nonlinear, especially when played fortissimo, so that stronger upper harmonics are produced than would be predicted by linear filter theory. This result is quite unexpected by most acoustics researchers but is supported by recent measurements (by researchers in The Netherlands) which show that sharp-edged shock waves are produced in trombones when they are played intensely. As part the preparation of data for this talk I designed a new program steran which operates on two analysis files (one for the mouthpiece and one for the output) and computes the filter transfer function between them. Graphs of the transfer functions for pp, mf, and ff trombone tones were superimposed and presented in color using Tim Madden's new SNDAN color facility.
James Beauchamp and UIUC students and Alumni at the 1996 SEAMUS conference. (left to right Sal Percoco, Tucker Robison, Antonio Barata, Elizabeth Hinkle-Turner, Richard Power, James McManus, and James Beauchamp)
This semester I completed three compositions in the Computer Music Project: http://hack.edu (composed and realized with Andrew Walters), Simply Folk, and China's Sorrow. All three compositions deal with, in varying degrees, downloading sounds off the internet, and convoluting them, using the program SoundHack.
I also completed a Sonata for Violin and Piano, written in CAMIL, using Professor Heinrich Taube's program Common Music to generate midi files, which were opened into Finale in order to compile a score.
Currently I am working on my doctoral piece, OPpenheimERA, which is a dramatic work for large chamber ensemble, voices, and tape. The tape part, which is being realized in CMP is being generated through the use of M4C, and Professor James Beauchamp's monan/addsyn software system.
Over the course of this semester, I've written two CD reviews which will be appearing in Journal Seamus and CMJ respectively. I've also aided in the reconstruction of graphics for a lecture given by Lejaren A. Hiller, Jr. at Darmst=E4dt.
In August, I will be giving a paper at the 1996 conference of the American Chemical Society on the computer music of Lejaren Hiller. I will also be participating on a panel that will discuss the similarities and differences between Computer-Assisted Composition, and Computer-Assisted Chemistry.
This semester I've completed the first three modules of melodic tone row dictation material for CASPAR. Harmonic tone row dictation material is currently in development.
I started 1996 by cleaning up Metropolis Mutabilis so that it could at last be submitted to Professor Scott Wyatt to satisfy the commision.
Hard on the heels of Metropolis, I began working on my other "city-inspired" piece, Voitures for amplified oboe and tape. Written for Melissa Pena, it was performed twice by her during this semester at the University of Illinois. On May 12, Ruby Ashley (of the National Symphony Orchestra of Ireland) gave its Irish premiere at the Hugh Lane Municipal Gallery of Modern Art in Dublin. At present, I am up to my eyes in a piece for flute and tape (for Camilla Hoitenga) and another more raucous piece for bass trombone and tape (for Rocco Quaranta). My piece for amplified ensemble and tape is still brewing away in the background. Voitures, Metropolis and the piece for bass trombone and tape will be used in this larger piece.
In August I shall leave the University of Illinois to go to the Insitute of Sonology at the Royal Conservatory of the Hague, Netherlands. The Kate Neal Kinley Fellowship (which I won in May) will help pay for my keep.
Christopher Preissing is an associate faculty at Indiana University South Bend. Since the beginning of the year he has had performances at the Indianapolis Art Center (January 13, reviewed in the March issue of New Art Examiner), Indiana University South Bend (January 19 and February 29), Beloit College with the Chelonia Dance Company where he also conducted 2 workshops on composition for multiple art forms and collaborative relationships (February 7-10), Birmingham-Southern College as part of the SEAMUS National Conference (April 19), Moreau Center for the Arts, Saint Mary's College, South Bend (April 21), Indiana Repertory Theatre, Indianapolis (June 13-15), and Indiana University Bloomington as part of Crossroads of Traditions sponsored by the Latin American Music Center and the United States Information Agency (June 30). Recent awards and grants include an Arts Projects and Series Grant from the Indiana Arts Commission for an interdisciplinary arts project titled Fragments which will be presented in Indianapolis on June 13-15, a Meet the Composer/Midwest Grant from Arts Midwest, a Beloit Professional and Program Development Committee Grant, and an Associate Faculty Grant from Indiana University South Bend. He has completed a composition for stereo tape (Jeu de l'oie), a work for stereo tape choreographed by Jane Hawley and premiered by the Chelonia Dance Company at Beloit College, Wisconsin (from beginningless time) and a multi-media presentation in collaboration with Susurrus, Inc. and Saints Neo-Vaudville (Fragments). This summer he plans to complete the chamber opera Thunder, Perfect Mind which will be premiered in November in Minneapolis, Minnesota.
Sever Tipei presented his ENVIRONMENT FOR MUSIC COMPOSITION at the Supercomputing 95 Conference and Trade Show, in San Diego, CA, December 1995, as part of the Argonne National Laboratory exhibit booth.
In January 1996 he also started a project to visualize original computer music compositions in the CAVE, a virtual environment available at ANL, NCSA and at the University of Chicago. The project, pursued with the help of graduate CS students Dave Blumenthal (one of the authors of the parallel version of M4C) and Max Levchin, involves the creation of Manifold Compositions or multiple variants of the same work. Tipei wrote a computer-assisted composition program, Manifold, containing some of the features available in MP1 but simpler, which produces the manifolds. The sounds are generated with DIASS_M4C running on the ANL's IBM POWERparallel System (SP), a cluster of 128 RS-6000 computers. The graphics run on SGI machines attached to the CAVE.
Also since January 1996, Jose Rosario, a CS student working for the Argonne National Laboratories, has developed a Graphic User's Interface (GUI) to access the DIASS scorewriter/editor. Written with Tcl-Tk, the interface allows now for much easier ways to enter data and edit DIASS_M4C scores.