The organ in the Old First Church was built by the Aeolian-Skinner Organ Company of Boston in 1958, their Opus 1326. The instrument consisted of 56 ranks and 3,241 pipes with a three manual console. It was designed by Dr. Charles Schilling, Organist and Choir Director of the Old First Church, and G. Donald Harrison, President and Tonal Director of Aeolian-Skinner. The Berkshire Organ Company later added several additional ranks including a Harmonic Flute, Sesquialtera and Trompette en Chamade.
In 1997 Foley-Baker, Inc. of Tolland, Connecticut was selected to completely re-leather the organ, upgrade switching and combination action and design a new case. The polished tin pipes of the façade were made by the German firm of Laukhuff. The new casework of African mahogany was designed by Richard S. Hedgebeth and constructed in the workshop of Steve Beeching, Tolland, CT. The new combination action was provided by Classic Organ Works of Markham, Ontario.
The organ restoration and new facade were a gift of a member of Old First Church. Chancel modification was a gift of Ellen G. Biringer of Southfield, Michigan, honoring her parents and her husband. The project was completed in the Fall of 1997.