Everything else being equal, pianists with smaller hands are disadvantaged on the current keyboard in two main ways. Firstly, they are more likely to suffer from pain and injury. Secondly, a significant proportion of the piano repertoire is ruled out for them – they have greater difficulty learning difficult repertoire, with many pieces physically impossible for them to play. These two factors mean they are thus prevented from reaching elite performance standards.
Research and much anecdotal evidence indicates that pianists with hand spans of 8.5 inches or less would benefit significantly from a smaller keyboard. Using this metric, 23% of adult men would benefit and 87% of adult women! And evidence from adult men with spans of up to 9 inches suggests that even they prefer a 6.0 inch octave keyboard for some repertoire – particularly works written by composers with very large hands including Rachmaninoff, Liszt, Grainger and Vine.
Keyboards with narrower keys help to remove discrimination. A 5.5 inch keyboard (where each key is about 7/8 the width of a ‘standard’ piano key) removes the one inch advantage men have over women. The proportions of pianists with ‘small hands’ could be dramatically reduced if they were to have access to the 5.5 inch and 6.0 inch octave keyboards. http://smallpianokeyboards.org/how-many-adults-have-small-hands/
Children of either gender have hands even smaller than most adults but are currently forced to learn on a piano designed for men.
Ultimately, what is most important is the music itself – as experienced by the pianist and their audience. The listener hopes for a wonderful, transporting musical experience, and the pianist wants to be able to become ‘lost’ in the music rather than thinking about technical issues .
‘The ability to control the sounds at the piano, and this means producing lovely tone as well as finely shaped phrases with a wide range of dynamics, depends to a large extent on the ease with which we can play.’ (Max Cooke, 1985)
As recognised by Otto Ortmann back in 1929, ergonomic factors – including a pianist’s hands being reasonably well-matched to the keyboard – are a critical factor affecting technical ease. If a reduced-size keyboard enables a pianist to reach greater heights and the audience is transported along with them, then why deny the world pianos with narrower keys?
Boyle, R., Boyle, R. & Booker, E. (2015). Pianist Hand Spans: Gender and Ethnic Differences and Implications for Piano Playing, Proceedings of the 12th Australasian Piano Pedagogy Conference, Beyond the Black and White, Melbourne, July 2015. https://www.appca.com.au/proceedings/
Cooke, M. (1985). The Advanced Pianist’s Tone, Touch and technique. Allans, Melbourne, Australia.
Leone, C. (2015). Ergonomic Keyboards:Size does Matter. Piano Professional, EPTA (UK), Summer.http://www.carolleone.com/ergonomic-keyboards/
Leone, C. (2015). Size is Key. Clavier Companion, Frances Clark Center for Keyboard Pedagogy, USA, September/October. http://www.carolleone.com/ergonomic-keyboards/
Leone, C. (2017). Personal Touch. International Piano, UK, January-February 2017. http://paskpiano.org/wp-content/uploads/2020/09/Int-Piano-Jan-2017.pdf
Ortmann, O. (1929). The Physiological Mechanics of Piano Technique. Kegan Paul, Trench, Trubner & Co., London, and E.P. Dutton & Co., Inc., New York.
A bibliography is available here: http://paskpiano.org/wp-content/uploads/2019/04/Alternatively-sized-piano-keyboards-Bibliography_April-2019.pdf