The organ at Memorial Church, Stanford University, Opus 85, combines elements from the Renaissance and the Baroque. This dualism shaped the tonal design and extends to the tuning of this unique organ. By means of five additional pipes in every octave, a large lever can switch the Werk, Ruckpositive, Seitenwerk, and Pedal divisions from a Renaissance fifth-comma meantone to a well-tempered tuning like those J. S. Bach knew. The Brustpositive and the Brustpedalia are fixed in meantone and offer two sub-semitones, or split sharps, per octave, D sharp/E flat and G sharp/A flat. Meantone tuning expert Harald Vogel worked closely with Charles Fisk during the development of this system and shared much valuable knowledge.

The Brustpositive is centered above the console; to the left and right are the halves of the Brustpedalia. Hand-operated doors for the Brust openings allow for dynamic control. The three large towers and two flats overhead contain the Great, or Werk, with 16' C of the Prestant in the center. The two smaller outside towers and the flats connecting them to the main case enclose the Seitenwerk, an Oberwerk on the sides of, rather than above, the Werk. The Rückpositive is divided between two cabinets at console level cantilevered beside the organist's platform.

The case is of red-stained poplar. The natural keys are grenadil and the accidental keys are rosewood capped with bone. Both functional and decorative, the polychrome and gilt pipe shades designed and carved by Roger Martin, feature a sea motif connecting the organ's origin in Gloucester to its home near the west coast.

Opus 85 is the last organ that Charles Fisk saw in the workshop. After a three-month installation at Stanford, the crew took photographs to show him this very special instrument in its new home. To the great grief of everyone in the shop, he died December 16, 1983, the day before the crew returned to Gloucester.