Page 43 - Summer 2007

Fig. 6a. Close-up showing micro-timing.
relation between motion and rhythm started in the early 20th century. Seashore (1938) and Gabrielsson (1987) both include a variety of reports, insights and opinions about this phe- nomenon. In this example, the tam- borim plays the first beat right on top of the pandeiro on the “real” downbeat, instead of playing at the “standard” temporal location for the note. This portion of the batida starts its repetition at the ninth event location (time 2000, triplet pickup to downbeat), just before the main downbeat, marked by the
black line at time 2050. You can see that the first beat ordi- narily is on the triplet pickup to the downbeat, and the next two beats are almost exactly evenly spaced on the subsequent triplet time points. The slight variations from playing exactly on temporal locations that correspond to a standard subdivi- sion are part of the swinghee style. While one might think that this is rhythmic looseness similar to the Graceland example, generally Brazilians play these slight temporal variations quite precisely, consistently and intentionally.
Conclusions and future work
Swing is a far more complex part of the musical land- scape than reported previously in the academic computer science literature. The authors have analyzed Swing rhythms in American, Jamaican, and Brazilian music. Some of these are simple enough to allow a complete assessment of the musical features that give rise to Swing feeling. Others point in the direction of subtle complexities that require improvements to the pattern recognition and signal processing techniques to characterize fully the Swing details described in this article. There are many other musical styles which have Swing characteristics including Cuban, Middle Eastern, African, Funk, and Hip Hop. Our analysis results clearly point to a basic inadequacy of standard Euro- American musical notation to annotate swing rhythm styles. Comments and observations from professional musi- cians agree with this notational limitation. For the purpos- es of musical analysis in the context of music information retrieval (MIR), the authors feel that it is more fruitful to omit most attempts to render a musical performance as tab- lature. It would be more practical and accurate to maintain the information in a form which is close to the actual audio data, and the information features that can be extracted from such recordings.AT
References for further reading:
Birch, Alisdair MacRae (2003). “It Don’t Mean a Thing If It Ain’t Got that Swing,” Just Jazz Guitar Magazine, August 2003. Online: http://www.alisdair.com/educator/musicarticles.html.
Cholakis, Ernest (1995). Jazz Swing Drummers Groove Analysis. Numerical Sound. Online: http://www.numericalsound.com.
Friberg, A., and Sundstrom, J. (1999). “Jazz drummers’ swing ratio in relation to tempo,” J. Acoust. Soc. Am. 105, 1330(A) (1999).
two phrase batidas to be played with the two phrases swapped. This is analogous to the 3-2 clave and 2-3 clave style in Cuban music. Swapping the sides gives a different feel, usually more syncopated if the unfamiliar variant is played.
The tamborim batida is very syncopated even when played straight. The “standard” place to start the basic tam- borim batida is at note event #6 in Figs. 6 and 6a at time location 1700, very slightly ahead of the beat. Many batidas have beats played ahead of the standard subdivision beat, and/or also slightly ahead of, or behind the note events of other instruments. In this example, the pandeiro plays about 30 milliseconds ahead of the standard downbeat at this temporal location, and the tamborim plays about 15 milliseconds ahead of the pandeiro. This technique is used to give a push to the feeling of the rhythm by both instru- ments. A few beats on either side of the 1700 point, both instruments play notes exactly on a standard subdivision. The feeling of this pattern is consistent throughout the sam- ple which is several minutes long. Figure 6a shows a closer view of the micro-timing.
The 15 to 30 millisecond time variations are on the order of 1/64 or 1/32 notes at the typical quick Samba tempo of 140 beats per minute. We believe from our experience with Brazilian music that the musicians are playing these timing variations entirely by intuition and experience, rather than explicitly subdividing the beat in the moment, i.e., by feeling rather than analysis. We have found that analytical under- standing has substantially improved our ability to play and hear these rhythms, but that in the performance too much analysis actually impedes our ability to play the groove well.
Looking at the two sets of three evenly spaced notes start- ing at 1700 and 2000, observe that the first and third beats are slightly ahead of the standard subdivision. These beats push the rhythm slightly and give a somewhat more energetic feel- ing to the music than if they are played straight. In this case, these two tamborim note events are also accented, further emphasizing the push to the rhythm at these two time points. The combination of time push and accent are caused by the tamborim player putting a little extra “juice” into the rhythm for these note events. Waadelund (2004) has studied the rela- tion between this type of “body english” and the rhythms played by drummers on drum kits. The investigation of the
Technical Anaylsis of Swing Music 41