Pedal note.

The lowest of the series of notes that can be sounded on a brass instrument with a given setting of any slide or valves. The term derives from the association of deep sounds with the pedals of an organ. The lowest octave of the serpent and the ophicleide consists of pedal notes (C–c for the most common size). Pedal notes have been used on the trombone from Berlioz onwards: on the B trombone, the pedals are B' down to E'. French horns with shorter tube lengths (such as the B side of the double horn) can sound pedal notes easily; they are difficult on instruments with longer lengths such as the horn in 12' F. Pedal notes are used frequently on tubas and euphoniums, but rarely on trumpets and cornets, and then only in showy solos. For instruments with a high proportion of cylindrical tubing, such as trombones, the air column does not have a mode of vibration at the correct frequency to support the fundamental (first harmonic) of the pedal note, which can only be sounded because of a ‘co-operative regime’ in which its higher harmonics are supported by higher modes of resonance of the tube. As a result, these pedal notes have a bright but hollow tone quality.

See Acoustics, §IV.

ARNOLD MYERS