A new scientific study published in Scientific Reports has sparked debate among musicians and listeners alike by suggesting that jazz may have become structurally simpler over time.
The research analysed more than 21,000 pieces of Western music across genres including jazz, classical, pop, rock, electronic music and hip hop. Using mathematical models and MIDI data, researchers examined the relationships between notes, harmonies and melodic movement across several centuries of music history.
Their conclusion was striking: jazz and classical music, once among the most structurally varied genres in the dataset, have gradually shifted toward more repetitive harmonic and melodic patterns — in some ways becoming mathematically closer to genres such as pop and rock.
That does not mean modern jazz is “bad”, less expressive or less creative. In fact, both the researchers and outside commentators repeatedly stress that point. But the findings do raise an interesting question:
Has jazz genuinely become less complex over time — or has musical sophistication simply moved somewhere else?
What the study analysed
The researchers, led by computational social scientist Niccolò Di Marco of the University of Tuscia in Italy, used MIDI files to analyse note sequences, harmonies, timing and melodic relationships. MIDI does not capture audio itself, but rather the underlying musical information: which notes are played, when they occur, how long they last and how they relate to one another.
From this data, the team mapped networks showing how notes connected and interacted within compositions. Older jazz and classical music tended to display more varied and less repetitive structures. But when researchers traced those patterns across time, they found a gradual trend toward simplification in certain measurable areas.
According to the study, classical and jazz music from the first half of the 20th century showed particularly rich and varied harmonic and melodic structures. Bebop-era jazz — with its rapid chord changes, substitutions and improvisational complexity — naturally sits near the centre of that period.
In later decades, however, the researchers identified increasing repetitiveness in harmonic movement, intervals and melodic patterns.
This is where the story becomes especially interesting for jazz fans
The study is not claiming that musicians today are less talented than the likes of Charlie Parker, John Coltrane or McCoy Tyner. Nor is it suggesting that modern jazz lacks sophistication or emotional depth. Instead, it focuses narrowly on measurable musical structures.
That distinction matters.
Jazz today often places enormous emphasis on areas that are difficult — or impossible — for this kind of mathematical analysis to capture:
- sound design
- rhythmic feel
- timbral experimentation
- electronic textures
- production
- collective interaction
- atmosphere
- cultural context
A modern ambient jazz recording, for example, may use relatively static harmony while still being sonically and emotionally complex in ways a MIDI analysis cannot properly measure.
The researchers themselves acknowledged this limitation directly, stressing that the study concerns the “mathematical framework of music” rather than the emotional listening experience itself.
The Evolution of Jazz Music
That nuance is important because jazz has always evolved according to changing cultural and technological conditions.
Speaking to Science News, Di Marco suggested that modern digital technology may partly explain the shift. Today’s musicians work in an environment shaped by:
- streaming
- DAWs
- algorithmic recommendation systems
- near-unlimited access to recorded music
- loop-based production
- digital composition tools
Di Marco also referenced separate research suggesting that album cover design has similarly moved toward minimalism over time.
Some commentators interpret these trends as evidence of a broader “cultural gray-out”. But not everyone agrees.
Friedlind Riedel, a cultural musicologist at the University of Salzburg quoted in the article, argues that fears about simplification have existed throughout music history. She notes that modern listeners arguably have access to a wider range of musical styles than at any previous point in history.
And jazz itself offers plenty of counterexamples to any simple narrative of decline.
Even within contemporary jazz, there are musicians exploring:
- advanced rhythmic systems
- microtonality
- dense orchestration
- electronic manipulation
- highly abstract improvisation
Meanwhile, many listeners would argue that emotional communication and sonic identity matter far more than harmonic density alone.
After all, a sparse Miles Davis phrase can sometimes carry more emotional weight than pages of virtuosic substitutions.
What really changed?
Perhaps the most interesting aspect of the study is not the claim that jazz has become “simpler”, but rather the suggestion that musical complexity may have migrated into different areas entirely.
In the bebop era, sophistication often lived in harmony and rapid improvisation. Today, it may increasingly appear in:
- production
- texture
- rhythm
- spatial sound
- genre blending
- electronic manipulation
- collective atmosphere
The language of complexity may simply have changed.
Still, the findings are likely to provoke debate among jazz fans — especially those who feel modern jazz has moved away from the harmonic adventurousness of earlier eras.
Was the bebop and post-bop period truly a unique peak of structural complexity in jazz history?
Or are today’s musicians simply speaking a different musical language altogether?
Either way, the study offers a fascinating reminder that jazz history can now be explored not only through records and biographies, but through mathematics as well.
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