Jankó keyboard

Lore & Background

Paul von Jankó, a Hungarian pianist and engineer, designed the Jankó keyboard in 1882 to address two limitations of the traditional piano keyboard: the difficulty of stretching beyond a ninth or octave for pianists with small hands, and the need for different fingerings for each scale. The keyboard features an array of keys with two interleaved manuals and three touch-points per key lever, resulting in six rows. Each vertical column of three keys is a semitone apart, and within each row the interval from one note to the next is a whole step. This layout allows each chord and scale to have the same shape and fingerings regardless of key, and the multiple rows accommodate different finger lengths. The keyboard retains traditional coloring (white naturals, black sharps and flats) for pedagogical purposes. For an 88-note keyboard, there would be 264 keys, with each note playable by three keys in vertical alignment. The keyboard is 89 cm wide, compared to 123 cm for a traditional keyboard.

Reader's Guide

The Jankó keyboard caused a stir at the time of its invention due to its unique look and intelligent design. American piano manufacturer Decker Brothers put it into production around 1891, and the Paul de Janko Conservatory of Music was established in New York around the same time. A manual titled How to Play the New Keyboard was written by W. Bradley Keeler. Despite this, the keyboard never achieved wide popularity. Music educators were not convinced the benefits outweighed those of the traditional keyboard, and few performers were willing to relearn their repertoire with entirely different fingering. Keyboard instrument manufacturers feared investing in a redesigned keyboard with only marginal commercial success. In the 1920s, pianist Carl F. Schmitt, a former student of Jankó, reported that the keyboard was taken up by pianists in Vienna, Leipzig, and Dresden, and its study was made optional in leading conservatories there. He noted the chief advantage was its truly chromatic nature, making all keys equally convenient to play and allowing transposition by simply starting in a new key. He also mentioned that the keyboard provided plenty of room for stout fingers. Many embodiments have appeared since, with patents filed by various inventors including John Trotter (1811), William A. B. Lunn (1843), and others through 1945.

Did You Know?

• The Jankó keyboard has six rows of keys, with each vertical column of three keys a semitone apart.
• For an 88-note keyboard, the Jankó layout requires 264 keys, each note playable by three keys.
• American piano manufacturer Decker Brothers put the Jankó keyboard into production around 1891.
• Carl F. Schmitt, a student of Jankó, reported that a young lady performed concerts on the Jankó keyboard after only six months of practice.

The Geometry of the Grid

Paul von Jankó, a Hungarian pianist with an engineer's mind, set out in 1882 to solve two problems that had plagued keyboard players for generations: the physical reach required for wide intervals and the ever-shifting fingering demands of different keys. His answer was to abandon the single-row paradigm entirely. The Jankó layout arranges two interleaved manuals so that every key lever presents three distinct touch-points, yielding six visible rows. Within any one row, neighboring notes are a whole step apart; vertically, each column of three keys is offset by a semitone from the columns in the alternate rows. For a full 88-note instrument this produces 264 individual keys, yet the overall width shrinks to 89 centimeters—roughly two-thirds of the 123-centimeter span of a conventional keyboard. The smaller key size means a pianist with modest hand dimensions can comfortably span intervals that would be impossible on a standard piano. The design also preserves the familiar white-and-black color coding so that existing pedagogical materials remain partially transferable.

Chromatic Uniformity and the Transposition Revolution

The most celebrated consequence of the Jankó grid is that every scale, chord, and melodic figure retains an identical shape and identical fingering no matter which key it is played in. Carl F. Schmitt, a former student of Jankó himself, articulated this point vividly in the 1920s: on a conventional piano, the major third D–F♯ occupies a noticeably different keyspace than the comparable major third B–D♯, a discrepancy of roughly a quarter inch that accumulates across thousands of passages. On the Jankó keyboard, such inconsistencies vanish. Passing the thumb under a black key after a white key feels exactly as natural as the reverse, because no key is inherently more difficult than another. Transposing an entire piece simply means starting the fingers in the new key and letting them move as before. Schmitt argued that technical mastery in one key automatically transfers to all others, dramatically reducing the practice time a pianist must invest. A seventeen-year-old student reportedly won critical praise in Europe's major musical centers after only six months on the new layout.

A Brief, Noisy Life in the Marketplace

When the Jankó keyboard first appeared, its striking visual appearance and the logic behind its design generated considerable excitement. Around 1891 the American firm Decker Brothers began producing pianos fitted with the layout, and the Paul de Janko Conservatory of Music opened its doors in New York. A dedicated instructional manual, How to Play the New Keyboard, was authored by W. Bradley Keeler. In continental Europe the instrument found a foothold in Vienna, Leipzig, and Dresden; leading conservatories made its study optional, and dedicated Jankó societies were formed. Prestigious German and Austrian manufacturers, including Blüthner and Bösendorfer, supplied Jankó-equipped instruments to the trade. Yet the novelty never translated into lasting commercial traction. Educators doubted the advantages were sufficient to upend entrenched teaching methods, and working performers were unwilling to relearn their entire repertoire under a new fingering system. Faced with what manufacturers perceived as marginal commercial upside, the industry simply refused to invest. By the mid-1900s the keyboard had, in Schmitt's phrase, gone to sleep after a life of about twenty years.

Patents, Predecessors, and the Long Shadow of the Idea

Jankó's original 1882 design was refined through successive patents. His first German patent, number 25852, filed on 14 January 1884, specified key shapes that echoed the slim profile of a standard piano's black keys. A year later, German patent 32138 of 1 July 1885, broadened and shortened those keys. The idea, however, did not spring fully formed from Jankó's mind. An English patent by John Trotter in 1811 described a concept substantially similar to the interleaved-row principle, and in 1843 William A. B. Lunn, working under the name Arthur Wallbridge, devised a sequential keyboard with two parallel rows of whole-tone keys. Miguel Theodore de Folly also filed a related patent. Since Jankó's conception, numerous other inventors have filed patents for keyboards that differ from his primarily in key shape or in the type of instrument to which they are attached. The Jankó layout thus sits within a longer lineage of attempts to make the chromatic scale geometrically uniform, a problem that has continued to attract designers well beyond the instrument's commercial failure.