Grand and upright: the hammer has to get back

“The releases are just as important as the attacks,” writes pianist and teacher Alan Belkin about Scarlatti’s Sonata in D Minor, K. 141. Its rapid repeated notes require fingers to get out of each other’s way. Fast downward movement is only half the task.

Inside the instrument, something else has to recover too. Yamaha’s guide contrasts the horizontal layout of a grand with an upright’s vertical strings. The grand’s hammer strikes upwards and falls back under its own weight; the upright relies on a spring to bring its hammer back. Saving floor space changes the mechanics as well as the shape.

The grand’s repetition mechanism makes a further difference. As Yamaha explains, another strike becomes possible before the key has risen fully and the hammer has returned to rest. A player can release the key less far before repeating the note. The mechanism offers a shorter route, not a substitute for coordinating the fingers.

Nor is the case shape a complete ranking of instruments. Steinway identifies a problem in a conventional upright: on release, the hammer lags behind the other action parts. The company describes a redesigned action intended to reduce that lag. This is a maker’s account of a particular solution, not evidence that every upright behaves like a grand.

Martha Argerich plays the linked Scarlatti sonata. It is a musical example of repeated notes, not a comparison of piano actions. Follow how a single pitch becomes a rhythmic figure. Each fresh attack also depends on a movement that an audio recording cannot show: the key being released in time for the next one.