modulation

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. The act or process of modulating.
2. n. The state of being modulated.
3. n. Music A passing or transition from one key or tonality to another.
4. n. Music The result of such a transition.
5. n. A change in stress, pitch, loudness, or tone of the voice; an inflection of the voice.
6. n. An instance of such a change or an inflection.
7. n. The harmonious use of language, as in poetry or prose.
8. n. Electronics The variation of a property of an electromagnetic wave or signal, such as its amplitude, frequency, or phase.

Century Dictionary and Cyclopedia

1. n. The act of modulating The act of modifying, adjusting, or adapting.
2. n. The act of inflecting the voice or any instrument in a musical manner.
3. n. The modification of the voice or of utterance to express various shades of meaning or emotion.
4. n. A state or condition reached by a process of modulating, modifying, or varying.
5. n. In Gregorian music, one of the tones in a mode with which every phrase of a melody in that mode must begin and end. The regular modulations of each mode include the final, the dominant, the mediant, and the participant, each of which has its own peculiar functions. (See these words, and also mode.) To these are added two other tones in each mode, called conceded modulations, which are of minor importance.
6. n. In modern music, the act, process, or result of changing, in the course of a piece, from one key (tonality) to another, so that a new tone becomes the key-note and the relative significance of all the tones common to both tonalities is altered. When a tone foreign to the original tonality of a piece is used, a modulatory effect is nearly always produced. If this effect is carried out into a cadence in the new key, the modulation is called final; otherwise it is passing or transient. All modulations, however, require a return to the original key before the end of the piece. The tone by which the transition is introduced or effected is called the note of modulation; this tone in the simpler forms of modulation is usually the fourth or the seventh tone of the new key. The simplicity of a modulation depends upon the closeness of relationship between the keys involved. The simplest modulations are into the keys either of the dominant or of the subdominant, and are effected by sharping the fourth tone or flatting the seventh tone respectively of the original key. Modulations into the relative minor or into the minor keys of the supertonic or of the mediant are elfected by sharping the fifth, the first, or the second tone of the original key respectively. Numerous other more intricate modulations are possible, especially in instrumental music. A modulation is abrupt, distant, or extraneous, when it leads into a key not closely related with the original one. It is deceptive when it utilizes a series of chords in an unusual and startling way. It is melodic when produced by the introduction of a tone foreign to the original tonality, and harmonic when produced by the use of a chord common to both tonalities first in its relation to one and then in that to the other. It is enharmonic when it is effected on an instrument of fixed intonation, like the pianoforte, by calling a key (digital) first by one name and then by another, as when E♭ in the key of B♭ is called D♮ in the key of B♮. Modulation is one of the most important resources of modern music. It introduces endless variety of both melodic and harmonic effect, with great possibilities in the way of sequences and imitations. It increases the unity of a composition and the importance of the original tonality by introducing a temporary disturbance of original tonal relations, with a subsequent complete and emphatic resumption of them. It affords means for the expression of very complex emotional conditions, particularly those of unrest, contrast, etc. In the style of Wagner it has often been pushed to the limit of toleration, so as almost to destroy that sense of fixed tonality which is the basis of musical certitude. The most remarkable harmonic convenience for modulation, at least in instrumental music, is a chord of four tones consisting of three minor thirds successively superposed, which is called the chord of the diminished seventh. This chord may be regarded as based upon any one of its four tones, which is then the seventh tone of either a major or a minor scale. Its harmonic nature is therefore peculiarly ambiguous and unstable.
7. n. A musical composition exemplifying modulation.
8. n. Sound modulated; melody.
9. n. In architecture, the proportion of the different parts of an order according to a module. Synonyms . Accent, etc. See inflection.

Wiktionary

1. n. The process of applying a signal to a carrier, modulating.
2. n. Methods of modulating.

GNU Webster's 1913

1. n. The act of modulating, or the state of being modulated.
2. n. rare Sound modulated; melody.
3. n. (Mus.) A change of key, whether transient, or until the music becomes established in the new key; a shifting of the tonality of a piece, so that the harmonies all center upon a new keynote or tonic; the art of transition out of the original key into one nearly related, and so on, it may be, by successive changes, into a key quite remote. There are also sudden and unprepared modulations.
4. n. (Electronics) The alteration of hte amplitude, intensity, frequency, or phase (of the carrier wave of a radio signal) at intervals, so as to represent information to be transmitted.

WordNet 3.0

1. n. (electronics) the transmission of a signal by using it to vary a carrier wave; changing the carrier's amplitude or frequency or phase
2. n. the act of modifying or adjusting according to due measure and proportion (as with regard to artistic effect)
3. n. a musical passage moving from one key to another
4. n. rise and fall of the voice pitch
5. n. a manner of speaking in which the loudness or pitch or tone of the voice is modified