The AGO pedalboard is a specification for the pedalboard on a pipe organ. It is part of the organ console specification promulgated by the American Guild of Organists. The specification calls for a pedalboard of 32 pedals, C-e', in a concave radiating pattern. That is, the fronts of the pedals (farthest from the organ console) are closer together than the backs, and the leftmost and rightmost pedals are elevated somewhat compared to the pedals in the center. The lengths of the pedals are specified, as is the length of the elevated section of the black notes, the height by which the black notes rise above the white notes, and the profile of the upper surface of the pedals. The specification is similar to the British RCO Pedalboard of the Royal College of Organists.
Prior to the widespread adoption of the AGO pedalboard, there was considerable variation in number, spacing, and geometry from one organ to the next. The use of the standard pedalboard makes it possible for an organist to play an unfamiliar organ without relearning the pedal layout.
Other layouts exist and some are still built, especially outside the United States. The Malines pedalboard is a concave-parallel design, and there are two "standard" BDO designs--one concave-parallel and one concave-radiating. The concave-parallel design is the more common of the BDO designs. The BDO pedalboards have 30 pedals.
The B-3 Hammond Organ used a pedalboard with minimal concavity and only 25 notes, though an AGO pedalboard was available as an option.
Many organs sold for the home market have a scaled-back pedalboard covering only 12 or 13 notes.
Pedalboard is the name of a large keyboard at the base of an electronic or pipe organ console that the organist plays with her feet.
Twenty-five and thirty-two note boards are the sign of a pipe or console organ; with these (especially the twenty-five note board) the organist may also confine her right foot to the expression pedal (or, with larger instruments, expression pedals), but they are designed to be played with both feet for optimum efficiency.
With shorter pedalboards designed to be played primarily with the left foot, for instance, the organist often greatly restricts or entirely omits the use of her heel, working the pedals with light touches of her toes; this allows her to range up and down the pedalboard quickly.