Currently, David Steinbuhler in Pennsylvania (USA) is the only manufacturer with many years experience with 5.5 inch octave (approx 7/8) keyboards (DS5.5®) and 5.1 inch (DS5.1®) for acoustic upright and grand pianos. David, and his grandson Alex, also make 6.0 inch octave (DS6.0®; approx 15/16) keyboards. In the case of keyboards for retrofitting grand pianos, careful measurements of the particular piano are required. They can be supplied with a new alternative action to allow for easy interchangeability or mounted on the old action. During 2018 the former Steinbuhler & Company was converted to a non-profit Foundation, the DS Standard Foundation Inc. (http://dsstandardfoundation.org/) however keyboard manufacturing remains an ongoing activity of the Foundation.
New Hailun HU1P upright pianos with DS5.5 or DS6.0 keyboards made by David Steinbuhler of the DS Standard Foundation are available through a partnership with Hailun USA: https://www.hailun-pianos.com/my-size-keys/. See also: Retail stores and pop-ups
New upright pianos manufactured by the Walter company (USA) (www.walterpiano.com) can be ordered with a DS keyboard installed.
Cunningham Piano of Philadelphia (www.cunninghampiano.com) now offers new “Matchless Cunningham” pianos with narrower keys (made by the DS Standard Foundation) on request.
Steinway & Sons USA will provide a narrower keyboard in new Steinway grands, or as a retrofit into an existing Steinway piano, on request. Please contact Hannah Reimann for further information: http://www.hannahreimann.com/stretto
David Rubenstein, from Los Angeles (www.pianosrubenstein.com) is willing to make alternatively sized keyboards and welcomes enquiries. dr@pianosrubensteinstein.com
Jim Watson, from San Marcos, Texas (www.watsonpianoworks.com) is willing to make alternatively sized keyboards and welcomes enquiries. Watsonpianoworks@gmail.com