Harmonic Polyrhythms Explained! [ AN's Bass Lessons #27 ]
Why Music: Practice & Theory Stack Exchange recommends it
Music Stack Exchange answerers point people to it for an audible demonstration that rhythm and pitch are the same phenomenon at different speeds, and that harmony is rooted in frequency ratios.
Recommended by 3 people across 3 different months, 2017 to 2018.
What it is
Adam Neely's bass lesson explains harmonic polyrhythms, showing how rhythmic patterns repeating at simple ratios mirror the harmonic series and can be sped up until they are heard as pitches and chords. He uses demonstrations you can hear, plus references to just intonation and wolf fifths.
What people said
Recommends ChipJust · 2017-04 · Music: Practice & Theory Stack Exchange · on “So... 84 modal scales vs actual practice and usage”
The Framework The framework for music is math, especially the harmonic series [LINK] . For rhythm, harmony and melody it is the mathematical relationship that creates the patterns that our brains look for when searching for meaning. Harmonic Polyrhythms Explained! by Adam Neely [this video] does a great job of explaining and illustrating this in a way you can hear. The meaning that our brains associate with these patterns is not just about math, however; rather we build up associations between certain math patterns and emotional or cognitive meaning. How much the association between specific patterns and meanings is objective or subjective is debated [LINK] , but most will agree that there is an
Recommends leftaroundabout · 2017-08 · Music: Practice & Theory Stack Exchange · on “Are there any musical pieces that experiment with the frequency - tempo relationship?”
Adam Neely did some [LINK] videos [this video] that explore the effect. I think Stockhausen also used it in some compositions, but I forgot which.
Recommends endorph · 2018-04 · Music: Practice & Theory Stack Exchange · on “What relation does harmony have to repetition?”
The other answers do a good job of outlining why harmony is generally not the same thing as rhythm. I wonder, though, if your question was provoked by videos such as these: If you haven't seen them, the presenter (Adam Neely) uses repeating patterns of notes, and speeds them up to produce a tone. If you have multiple patterns repeating at the right ratios, you get harmony. This works because of how sound works. You can consider any repeating rhythm as having a frequency; that is, the number of times it repeats per second. If a rhythm is fast enough (say 20 repeats per second, also called 20 Hertz), we start to perceive it as a sound. If you keep speeding it up, you hear it as a higher sound.
Cites Sarkreth · 2018-06 · Music: Practice & Theory Stack Exchange · on “Can a pitch be perceived outside the range where it can be heard?”
If I tap my hand on my desk at 5Hz, I hear the taps, but they're perceived as individual events, not a sustained note. The perception of pitch emerges when events happen fast enough. Here's a video about it, with a demonstration at the timestamp in the link : So the answer to your question is basically "no". Pitches below the normal hearing range are heard, but not as pitches .