CCRMA OVERVIEW - CCRMA - Stanford University

in a least-squares sense. Overcoming a significant limitation of the traditional approach in the art,
preliminary detection of spectral peaks is not necessary and the method works even when spectral
peaks are not well resolved in frequency. This allows for shorter analysis windows and therefore better
time resolution of the estimated sinusoidal parameters. Results have also shown robust performance in
presence of high levels of additive noise, with signal-to-noise ratios as low as 0 dB.
6.7.2 Visualizations of Tonality
Craig Stuart Sapp
Two-dimensional pictures of musical key taken over different time-scales in a piece of music will be presented.
Each key is assigned a different color related to the circle of fifths. Long-term key measurements
occur at the top of the plots, and the analysis window gradually decreases in width to one beat by
the bottom of the plots. The resulting pictures graphically display the hierarchical key structure of the
music and how the key relates to the underlying chords.
6.7.3 Audio Content-Based Retrieval Methods and Automatic Style Classification
Unjung Nam
The rapid proliferation of user accessable digital music data poses significant challenges to the tasks
of searching and retrieving music from massive data sets. Signal analysis methods to derive high level
musical information such as pitch and instrumentation could be used to formulate classification methods
that may prove useful in efficient and flexible content retrieval. My research evaluates some current
approaches to content-based music retrieval methods and proposes a model that attempts to distinguish
among three classes of music (jazz, popular, and classical) by analysis and extraction of features in the
frequency and time domains.
6.8 Historical Aspects of Computer Music
6.9
6.9.1 New Realizations of Electroacoustic Works
Chris Burns
There are a number of reasons to create new realizations of favorite electroacoustic works. First and
foremost are the reasons for performing any interesting piece of music. Performance creates the opportunity
to share the work with new audiences, and encourages close study of the work by the performer.
This engagement is especially important for indeterminate or otherwise flexible works which require the
performer to make decisions traditionally considered compositional. Additionally, many electroacoustic
works will eventually require rescue from technological obsolescence. New realizations, using new technologies,
can extend the performing lifespan of a piece with complex technical requirements. Finally, the
process of realization admits the possibility of an evolving, performing tradition for a particular work,
with new solutions and interpretations enriching the music s sense of possibility.
Two recent realizations by the author are useful case studies in the creation of new performing versions
of electroacoustic music. Although very different works, Alvin Lucier's I Am Sitting In A Room and
Karlheinz Stockhausen's Mikrophonie I present some similar challenges in realization. Both works have
relatively open, flexible scores which encourage experimentation and variation. They also have wellestablished
performing traditions, centered on the composer as authoritative interpreter, which have
minimized the flexibility suggested by the scores.
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