The Role of Temporal Fluctuations for Swing Feel in Jazz Music

In 1931, Duke Ellington and Irving Mills dedicated a song to the swing phenomenon, which they called “It don’t mean a thing, if it ain’t got that swing”. Yet to date, the question of what, exactly, makes a jazz performance swing has not really been clarified. A team from the Max Planck Institute for Dynamics and Self-Organization in Göttingen and the University of Göttingen recently conducted an empirical study of the role played by microtiming in this process, a topic so far controversial among music experts and musicologists. Experts refer to tiny deviations from precise timing as “micro-timing deviations”. The project team has now clarified the role of microtiming deviations for “swing feel” using digital jazz piano recordings with manipulated microtiming that were rated by 160 professional and amateur musicians for feel. swing.

Jazz, but also rock and pop music can literally carry listeners away, causing them to involuntarily tap their feet or bob their heads in time with the beat. In addition to this phenomenon, known as “groove”, jazz musicians have used the concept of swing since the 1930s both as a style and as a rhythmic phenomenon. However, to this day, musicians still struggle to say what swing actually is.

In his introduction “What is swing? for example, Bill Treadwell wrote, “You can feel it, but you just can’t explain it.” Musicians and music lovers have an intuitive idea of ​​what swing means, but so far musicologists have mainly characterized one of its obvious characteristics: rather than successive eighth notes sounding for the same duration, the first is held longer than the second (the oscillating note). The “swing ratio”, i.e. the duration ratio of these two notes, is often close to 2:1, and it tends to shorten at higher tempos and to lengthen at tempos weaker.

Swing ratio fluctuation

Musicians and musicologists also refer to rhythmic fluctuations as one of the particular characteristics of swing. Soloists, for example, sometimes play distinctly after the rhythm for short periods, or “casual,” to use technical jargon. But is it necessary for the swing feeling? Researchers have also studied much smaller temporal fluctuations that can escape the conscious attention of even experienced listeners. Some musicologists argue that such microtiming discrepancies (e.g., between different instruments) define swing. But the researchers in the current study came to a different conclusion. They suggest that jazz musicians feel the swing slightly more when the swing ratio fluctuates as little as possible during a performance.

The mystery of the swing sensation motivated the researchers, led by Theo Geisel, director emeritus of the Max Planck Institute for Dynamics and Self-Organization, who also plays jazz saxophone. He says, “If jazz musicians can feel it but not explain it precisely, we should be able to characterize the role of microtiming deviations operationally by having experienced jazz musicians evaluate recordings with the timings original and systematically manipulated.”

Microtiming deviations are not an essential component of the swing

As a result, the team recorded 12 tracks by a professional jazz pianist played over pre-generated precise bass and drum beats. The researchers manipulated the timing in three ways. For example, they eliminated all deviations in the pianist’s microtiming throughout the piece, that is, they “quantized” his performance; they then doubled the duration of the microtiming gaps, and in the third manipulation, they reversed them. So if the pianist played a swing note 3 milliseconds before the average swing note of this piece in the original version, the researchers shifted the note by the same amount, or 3 milliseconds behind the average swing note, in the reversed version. Subsequently, in an online survey, 160 professional and amateur musicians rated how natural or flawed the manipulated tracks sounded, and the degree of swing in the samples.

Geisel says, “We were surprised, because on average, participants in the online study rated the quantized versions, i.e. those without microtiming deviations, as slightly more oscillating than the originals. , microtiming deviations are not a necessary component of swing.”

Coins with doubled microtiming deviations were rated by survey participants as the least oscillating. “Contrary to our initial expectations, the reversal of microtiming time deviations only had a negative influence on the ratings for two tracks,” explains York Hagmayer, a psychologist at the University of Göttingen. The amount of swing each participant attributed to the tracks also depended on their individual musical backgrounds. Regardless of track and version, professional jazz musicians generally gave slightly lower swing ratings.

At the end of the study, the researchers asked the participants for their opinion on what makes a room swing. Respondents cited factors such as dynamic interactions between musicians, emphasis, and the interplay between rhythm and melody. “What has become clear is that although rhythm plays a major role, other factors, which should be investigated in further research, are also important,” says Annika Ziereis, first author of the paper. with George Datseris.