Double whole note the "brevis" was to be considered the unit of time ("tactus"), instead of the usual "semibrevis". The old symbol , used as an alternative to the numerical proportion 2:1 in mensural notation, is carried over into modern notational practice to indicate a smaller relative value per note shape. It is normally used for music in a relatively quick tempo, where it indicates two minim (half note) beats in a bar of four crotchets (quarter notes), while is the equivalent of , with four crotchet beats . Double whole note In music, a double whole note (American), breve (international), or double
Two hundred fifty-sixth note long as the two hundred fifty-sixth note. After this would come the one thousand twenty-fourth note (eight flags or beams), the two thousand forty-eighth note (nine flags or beams), the four thousand ninety-sixth note (ten flags or beams), and so on indefinitely, with each note half the length of its predecessor. The shortest note value to have ever been used in a published work is the 1024th note (notated incorrectly as a 2048th) in Anthony Philip Heinrich's "Toccata Grande Cromatica" from "The Sylviad", Set 2, written around 1825; 256th notes occur frequently in this piece, and some 512th notes also