Most piano students experience the nemesis of hard-falling, accident-prone thumbs during their scale and arpeggio romps. If unchecked, these power-grabbing fingers of each hand have a tendency to interrupt smooth-playing keyboard journeys.
As a start, a player should imagine a scale or arpeggio as a seamless outflow without “bumps” or undesirable “accents.” Even in a transition to staccato, the emboldened thumbs should be trained to be part of a team effort on the “playing” field, not outmaneuvering themselves.
To advance a collective ten-finger undertaking that tempers thumb-controlling dominance, I have students isolate thumb placements or arrivals (in ascending/descending scales and arpeggios) thinking “up,” NOT DOWN. In this pursuit, there’s a pleasurable “buoyancy” derived from an uplifting thumb that supports an overall sequence of well-balanced, well-spaced notes. If the player enlists relaxed arms and supple wrists along with embracing a consciousness of heaven-bound thumbs, then the results are noteworthy.
Blocking out notes that precede and follow LIGHTER thumbs is also a savvy approach to toning down any intrusions by these shortest fingers. In a clustering process that advances a “group feel” to a spree of notes, there should be thumb-tamed progress.
In short, even a simple teacher generated prompt such as “fold in” your thumbs will often eradicate unwanted accents.
In this Online Lesson-in-progress, a student in Scotland amply demonstrates how “folded-in” thumbs work beautifully through a tapestry of Bb minor Arpeggios in various forms. (including Diminished 7th renderings on A)
To listen to such a stream of well played arpeggios is as pleasurable as generating them (for one’s self) at the piano bench!
Here’s a bonus video on navigating the tricky Bb minor arpeggio in Contrary Motion using a blocking technique at the opposing end octaves. My thumbs are folded in during the course of this tutorial.