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Researchers from Tampere uncover the secret behind drumming legend Jeff Porcaro’s groove

Researchers at TUT and Harvard have recently published research findings that help us understand the components of that special ‘groove’ that makes certain songs and drummers stand out. The findings have direct applications to the development of drum machines and drumming pedagogy.
”This project has allowed me to combine my love for physics with my passion for music and especially rhythm and drums,” Esa Räsänen says.
”This project has allowed me to combine my love for physics with my passion for music and especially rhythm and drums,” Esa Räsänen says.

Researchers at Tampere University of Technology (TUT) and Harvard University have collaborated to analyse the music of drummer Jeff Porcaro on the millisecond scale. Jeff Porcaro (1954–1992) is one of the best known and most recorded drummers of all time. He was one of the founding members of TOTO and played on the albums of numerous rock, pop and jazz superstars, such as Michael Jackson, Madonna, Bruce Springsteen, Pink Floyd, Dire Straits and Herbie Hancock.

"An astonishingly broad range of dynamical or complex systems in various branches of physics, biology, and economics, such as heart beat, gait, tapping and drumming, exhibit fractal behaviour, or a pattern that repeats itself across different scales. This natural phenomenon can also be observed, for example, in the structure of cauliflower and the leaves of ferns,” says Professor Esa Räsänen from the Department of Physics at TUT.

According to Räsänen, earlier studies have demonstrated that people prefer music that sounds natural due to fluctuations in interbeat intervals. These ‘human’ fluctuations may contribute to the perception of groove.

The research especially focused on late Jeff Porcaro, perhaps the world’s best-known drummer, and his one-handed hi-hat drumming pattern in Michael McDonald’s song I Keep Forgettin’ recorded in 1982. The selected song is well suited for quantitative analysis, as the large number of onsets in hi-hats played on the 16th notes allows sufficiently reliable fractal analysis. In addition, the song is strongly driven by drums and bass that dominate the instrumentation in most parts of the recording. This helps the precise determination of the onset times. The researchers were able to identify fractal properties in both the temporal fluctuations and amplitudes of Jeff Porcaro’s one-handed hi-hat pattern.

“Long-range correlated temporal fluctuations in the beat of musical rhythms are an inevitable consequence of human action and have a positive effect on the listening experience” Räsänen says.

The findings open up new avenues for the development of drum machines. As the machines sound artificial compared to human drummers, software for computer-generated music has been tweaked to add random deviations to the beat to give it a more human feel, but the fractal dynamics of drumming have been ignored.

The research paper appeared in PLOS ONE on 3 June 2015.
Link to the paper:

Further information:
Professor Esa Räsänen, Tampere University of Technology, Department of Physics, tel. +358 50 301 3386,

News submitted by: Anna Naukkarinen
Keywords: science and research