Dictionary of Music - Birding America

ôtez 293ornaments, especially in keyboard and lute music,but there was still a great deal of confusion as tojust what each sign meant. Gradually the signsbecame more standardized, although they still variedsomewhat in different countries. Many of thesigns that came into general use throughout Europewere based on those used by French keyboard composersof the seventeenth century, who called themagréments.oscillator (o′si lā tər). An electronic circuit thatproduces an alternating-current voltage signal atsome specific frequency. In synthesizers and electronicsound systems, it is the oscillator that isresponsible for producing all sounds of a definitepitch. Unlike any musical instrument, it can producea sine tone, that is, a tone totally lacking in harmonics(overtones). In early synthesizers the oscillatorwas set to a desired frequency, the sound wasrecorded, turned off, and then the oscillator wasreset for the next pitch. This tedious process waseliminated in the early 1960s with the invention of asystem of voltage control whereby an electrical voltageitself was used to set an oscillator frequency.The device controlling the voltage-controlled oscillator,or vco, might be a keyboard, a strip of conductiveresistance ribbon, a joystick, a sequencer, oranother oscillator; when the last-named is used, thetechnique is called frequency modulation.ossia (ô sē′ä) Italian: “or else.” A term indicatinganother way of performing a passage, usually asomewhat easier way. Also, oppure, ovvero.fig. 173 p/u from p. 304Although since about 1900 most composers havetended to write out ornaments note for note, usingalmost no abbreviations except for the trill, knowledgeof the conventional signs is needed to performmusic of the seventeenth, eighteenth, and nineteenthcenturies. The most important ornaments are themordent, inverted mordent, double mordent, TRILL,turn, inverted turn, Nachschlag, ACCIACCATURA,GRACE NOTE, APPOGGIATURA; all of these are illustratedin the accompanying example.ostinato (ôs′′tē nä′tô) Italian. Also, British,ground, ground bass. A shortening of basso ostinato,a bass part that is repeated over and over throughout acomposition or section while the upper part (or parts)change. The ostinato serves to unify a composition,since it remains constant while the melody, harmony(chords), or counterpoint change. The practice ofusing an ostinato was very popular from the sixteenthto the early eighteenth centuries, especially in instrumentalmusic, much of which was based on dancemusic. However, outstanding examples in vocalmusic were written by Monteverdi (in Lament ofAriadne, 1608) and Purcell (in Dido’s Lament, fromDido and Aeneas, 1689). In the seventeenth century itwas common to improvise above an ostinato. Amongthe important musical forms based on a basso ostinatoare the chaconne, passacaglia, romanesca, folia,ruggiero, and passamezzo. (See also DIVISION, def. 1.)ôtez (ō tā′) French: “take off.” A word used insuch musical terms as ôtez les sourdines (“take offthe mutes”), or ôtez les boutons (“take off thestops”). Also, ôter.