In 1900, Melville Clark, an experienced reed organ and piano manufacturer, left his active partnership in the Story & Clark Organ and Piano Company, and set up on his own, as the Melville Clark Piano Company, in DeKalb, Illinois. In a very short time, his company was producing the Apollo Piano Player, which played 58 notes of the piano, and which could transpose to other keys, by means of a patented, sliding mechanism. The 88 note system was in development and the Upright Apollo player pianos were also in production, and the Company made a publicity feature of their 88-note capabilities. This pioneering quality only lasted until December 1908, however, when the majority of player manufacturers agreed, at a conference in Buffalo, New York, called by the A.B. Chase Company, to a set of mechanical standards for a new 88-note system, on which the spacing of the notes was set at 9 to the inch, allowing an 88-note roll to occupy the same width as the older 65-note variety. Newer and more sensitive mechanisms meant that the smaller perforations could still work as efficiently as the older and wider ones.
All Apollos used a patented clockwork motor to drive the music roll, wound up by a pneumatic attached to the player pedals. This is perhaps not ideal for tempo control, but it was very stable, and had the advantage of providing the player with a free ride during re-roll.
This allowed Melville Clark to experiment with fill-in ideas.
Perhaps the most complicated development of these ideas was where the normal Apollo player piano was combined with a phonograph – the Apollo-Phone, which used the same spring motor to drive both devices. When the player piano was not in use, the top half of the roll frame was used as a soundbox for the phonograph. It would appear, from the simplicity of the phonograph drive connections, that no attempt was made to synchronise the two devices.