Entasis is an ancient Greek term meaning “tensioning.” Speech that is delivered in a metrically perfect manner has the power to cause the listener's brain to shutdown and cease processing the meaning of what is being said...all within a few seconds of hearing such speech. The human brain needs the condition of constant or stable irregularity for it to remain alert and attentive: irregularity produces a state of alertness and attentiveness. Constancy or stability eliminates the feeling of discomfort which chaos, the erratic and irregular, often creates. The balance in tension between the feeling of predictability that constancy (stability) provides and the feeling of anticipation that irregularity and unpredictability creates a state of Entasis. The opposite of Entasis is Stasis or staticness. Entasis in normal human speech is brought about by the flow of thought, which is both irregular and constant. So it must be in music.

    The French, in the 17th and 18th centuries, understood the importance of entasis. This, we believe, is what the musicians who wrote about inégal meant by the term. The word actually means rough, irregular, unequal. The conventional interpretation of this word betrays its real meaning by forcing it to conform to the present fashion for perfect metricality in performance practice of old music - that interpretation suggests that inégal means perfectly regular limping. Had the French writers meant that, they would have used the term for limping. Otherwise, they would have used the phrase “égal inégal" or “equal unequal.” Therefore, we must take the term inégal at face value and understand it from a cognitive point of view.

    In music, cognitively speaking, every note played in a way that is predictable creates stasis. In stasis there is an absence of tension and, consequently, listening further to what is being played is pointless. Should performers fail to understand the entasis technique, the result is deadly because it virtually guarantees that the audience will be prevented from really paying attention to the music. In his treatise on Poetics (XXIV), Aristotle observed that "sameness of incident soon produces satiety." Similarly, anyone can observe that it takes only three notes of equal value with two equal spaces between them to create a condition of boredom in the brain. Within the time it takes to hear three notes, the brain has noticed that the second event is like the first, that the third is like the second and the first, and it predicts that the fourth will follow the pattern. As soon as that prediction comes true, the brain either goes to sleep from boredom or looks elsewhere for something more interesting. If this happens, as it usually does, in the brain of a performer, mistakes are the natural byproduct. To the listener, mistakes which occur in a static musical environment become the meaning instead of the music...a disaster. This is why musicians today who can't learn to play music without mistakes are discouraged by every means possible from performing in public.

    Learning to play music exactly according to a metronome is the major cause of performance anxiety. It is virtually impossible to try to avoid making mistakes when your brain has gone to sleep - avoiding mistakes is hard enough when your brain is fully alert. And when the mistakes become the meaning, which is always what happens, the groundwork for paralyzing fear of performing has been carefully and cleverly established. It is the reason why one might define talent in music today as the ability to play the right notes, exactly in time, with a brain that is fast asleep.

    Metrical exactitude in musical performance guarantees that most listeners are barred from experiencing the spiritual essence of great music. It also guarantees that music can only be heard and ignored by most people. It is the embodiment of slavishness in music...slavishness to the metronome...exactly the opposite of what CPE Bach, in his “Essay on the True Art of Playing Keyboard Instruments,” suggested when he wrote that one should "endeavor to avoid everything mechanical and slavish. Play from the soul, not like a trained bird." The entasis technique is the way out of slavery into freedom. It is simple to do: perform notes of equal value in any manner other than that which appears, feels, sounds, or can be construed as regular or equal.

    Using this technique presents problems, the greatest of which is that it can sound chaotic. Most musicians vehemently hate this effect; indeed, it is unpleasant.  However, there are other cognitive techniques, discussed in this essay, that are designed to create order and logic out of the chaos of totally irregular, unmetrical music making: the Gesture, Syntactical, and the Recognition Signal techniques. They create the feeling of logic, flow, and meaning when the techniques of Synaesthesia and Entasis are being applied. The second problem is that musicians have been bullied into playing metrically accurately for so long that playing not-metrically accurately on purpose is hard to do. It actually takes practice, as does the synaesthesis technique. But, as with all things, practice makes perfect...except in this case, one must understand that perfect is a feeling in the souls of the listeners, not an articulated fact in the accurate presentation of pitch and time value of each and every note in the score. Music must feel perfect. To be so, it must appear metrically imperfect.

    What, then, is the role of the beat? We feel that the beat should be felt and not heard. Like the beating of the heart, the musical beat needs to fluctuate in speed as the emotional content of the music fluctuates. Like the naturally shifting accents in speech, musical accents need to shift according to the meaning being expressed. As soon as the beat, meter, or accents become noticeably regular and unvarying, they appear too obvious and are in bad taste because they sound pedantic and academic.

    In this musical example, you will hear a Scarlatti Sonata played with Synaesthesis, Vacillare, and Entasis. Notice how the music appeals to our feeling more than our judgment.

Application: Avoid performing music in strict accordance with the beat. Avoid having ever more than three notes of equal value sound equally with equal spaces between them. Even two notes of equal value and space is enough to create a flattening of the listener's attention.

Domenico Scarlatti: Sonata in A Major. K. 208, Robert Hill, fortepiano after B. Cristofori (K. Hill, 1999). Recorded in May 2004