The Grand Piano Series

A Technical Outline of the Reproducing Piano

The first Reproducing Pianos went on sale in Germany in 1904. As their success grew the Aeolian Company - the largest piano maker in America - recognised it as an opportunity to sell more pianos. The result of their unique development, unveiled in 1913, was an advanced digital system for recording the playing of great pianists - called the Duo-Art.

Between 1915 and 1930 the Reproducing Piano was very big business. In its peak year, 1925, more than 192,000 domestic instruments were manufactured by the Aeolian Company in the USA, with a total sales value of $59,000,000. The Aeolian Company made every effort to perfect and enhance their invention, and throughout this period they kept the most famous pianists under contract; offering a balanced repertoire of smaller pieces, and, most significantly for us, larger works which the 78 rpm disc could not manage.

There was never any problem about recording the activation of keys and pedals via electric contacts on the recording piano. The clue to recording expression, or "touch", lies in the hammer speeds. Because the piano has an escapement action, once the key is struck, the hammer moves irresistibly to its destination. There were four methods in use to ensure dynamic accuracy.
  • Electric contacts at two points of the travel of each hammer measured its speed.
  • A gramophone record was kept for reference.
  • The recording engineer, sitting beside the pianist, entered his own notation into a console linked to the perforator.
  • After two editions of the piano roll had been made at the factory, the pianist had to check all details before the third edition was published. Correspondence survives, which shows how seriously pianists approached this task.
Reproducing Pianos are powered by an electric motor generating suction. This is piped to a tracker bar, pierced with one note for each piano key, plus further holes which direct the precise variations in air pressure to the tiny bellow operating each key. Playback, via a perforated paper roll, automatically controls the action of the keys, the synchronisation of the pedals, and the dynamic value of each note.

The "Robot" used for this new series of recordings is a free standing construction which is pushed up to the keyboard of a piano; in this case a Steinway Concert Grand. It was completed in 1973, specifically to present uninhibited reproduction on modern grand pianos. Its expression decoder is a unique special construction of the late Gordon Iles, inventor and chief theoretician of the Aeolian Company in England. Other working parts were made between 1925 and 1936 in the UK and America, but are now adapted to the new model. A simple but significant advantage of the Robot is in its correct application of the side-shift "una corda" pedal. Even though the action of the una corda was accurately recorded in the Duo-Art process all built in mechanisms (built into the piano, that is) substitute an inferior "half-blow" effect. This compromise of a very basic element of tonal control was made in order to conserve function power in the domestic models. In this and all other aspects the Robot incorporates the ultimate Duo-Art technology in order to deliver historic performances exactly as heard and approved by recording artists in the Aeolian Hall in the first quarter of this century.