Through experiments and study, 19th century physician Karl Von Vierordt proposed that as humans we overestimate short periods of time and underestimate longer periods. But there is an inbetween where we get the duration right, where error is close to nil. That sweet spot Vierordt referred to as the indifference point.
The indifference point has been calculated at 625 to 700 milliseconds. Musically speaking, that’s between 86 and 96 bpm on a metronome.
This came to my attention when Matthew Guerrieri used the indifference point in his book discussing Beethoven 5. Tempo of the first movement, as written by Beethoven, should be 108 bpm. Contrary to his markings, the average tempo (according to averaging sixty six recordings in 1998 by Gunther Schuller) of this movement is just shy of 92 bpm. That is right in the middle of the indifference point.
But there is that unique feeling one gets when listening to a performance that strives towards Beethoven’s tempo. Past the safety of the indifference point, one receives an overwhelming sensory experience. Either this push leads to delight or disgust.
Charlie Parker’s lightning tempo jazz, well beyond the indifference point, overwhelmed many who labeled his music as noisy and incoherent. But a host of people were lead into ecstasy, spawning a whole movement of admirers and emulators: bebop.
Then there’s IDM: intelligent dance music. This electronic music’s bread and butter is sheer velocity (this is a good example). With furiously quick drum breaks and punchy electronic sounds, it has been labeled by some as random talentless trash. “How does one write this stuff anyways?” is the usually remark. IDM, however, still goes strong with artists showing the possibilities and artistry that lies in the blistering bleeps and bloops.
These two types of music are largely hinged on tempo, both in style and reception. The reception being the critical part here. Case in point, speed affects us as we listen, leaving us in awe or with a headache. Faster tempo music has had this fascinating dichotomy. With Vierordt’s indifference point we can at least grasp at one part of a many pointed explanation.