The accentuation is an inflection of the bow-stick. In musical terms, we can picture it as a crescendo-diminuendo. For the accentuated détaché, this accentuation is done at the beginning of the bow stroke. The primary technique for inflecting the stick is to squeeze the thumb and forefinger together — however there is also a subtle rotation of the forearm inwards through pronation.
It is easiest to start learning the accentuation at the middle of the bow where the stick is most flexible. The accentuation should first be practiced forte before practicing piano. It is crucial to focus on actually producing an accentuation before attempting subtle accentuations.
Practice the following exercises:
- Press the stick all the way to the hair — do not draw the bow. Do this at the middle of the bow. Rotate your forearm instead of relying purely on finger strength. Practice also at the extremes, i.e. the point and the frog. Notice how the stick bends and how it differs from the middle.
- Practice producing a scraping sound. The point is to experiment and understand how much pressure the string can take. Press the stick down to the hair at the middle of the bow, and drag the bow across the string. Do this over the fingerboard and gradually work towards the bridge. Notice how not only different contact points can take different pressures but also different strings too. Notice how this changes in higher positions.
- Before attempting an accentuation, practice producing a sharp attack. Press the stick down, then draw the bow and immediately release the pressure. This will give a sharp attack. Practice producing a sharp attack with different pressures in all parts of the bow, both down-bow and up-bow.
- Finally, produce an accentuation through playing a crescendo-diminuendo by inflecting the stick. First, try the cresc-dim well after drawing the bow. Then try to do this immediately after drawing the bow. Practice in all parts of the bow both down-bow and up-bow.
The difference between the sharp attack and the accentuation is sometimes referred to as consonant versus vowel sound.
In order to master the accentuation, you should:
- practice inflecting the stick at all parts of the bow
- learn how much and how little pressure can be applied
- learn what bow speeds are possible for various pressures
- practice at various contact points