Modulation can consist of an alteration of the value of a wave amplitude, phase or frequency.
From the Latin modulatio , the term modulation is related to the fact and consequences of modulating . This verb has several applications and uses, such as altering the properties of a sound, changing the factors that affect a procedure to achieve different results, leaving one tonality to appeal to another or modifying the value of a frequency , phase or amplitude of a wave. .
For telecommunications , modulation are those techniques that are applied in the transport of data over carrier waves . Thanks to these techniques, it is possible to take advantage of the communication channel in the best way to transmit a greater flow of data simultaneously. Modulation helps protect the signal from interference and noise.
The modulation process consists of varying a parameter that is in the carrier wave depending on the alterations of the modulating signal. We can talk about frequency modulation , amplitude modulation , base modulation and wavelength modulation , among other types.
Modulation in music
In the musical field, modulation consists of altering the key momentarily , which is why it should not be indicated in the score with a new key signature, and it is possible to resolve it using a cadence, although it is not mandatory.
In general, we seek to move to close tonalities (not to be confused with the physical proximity of the notes on a staff, but rather that they are related in some direct way and that require the least amount of changes or " accidents " starting from the main one), although Sometimes you try to change modes (from high to low or vice versa) or for different intervals.
In music, modulation involves a momentary change in key.
Classification according to type
The three types of modulation currently taken into account are explained below:
* using a bridge chord : when it comes to neighboring tones, according to what was explained in the previous paragraph. The idea is to start with a chord common to both tonalities, and then perform a cadence to resolve to the desired destination. The simplest case, that is, the one for which no alteration is needed, is to go from a key to its relative minor or major, such as from C Major to A minor. On the other hand, the most complex is to modulate to a tone that shares only one chord with the original.
* through chromaticism : it consists of starting from a chord of the main key and altering a note chromatically (raising or lowering half a tone) to convert it into a chord of a new key, which is not related to the first. If, for example, you want to go from C Major to G minor (it should be noted that the G Major chord with its minor seventh is the dominant of C, which means that it occupies an essential role in said key, since there is a lot of tension between this and C, the tonic) it is possible to take a G Major chord and then convert the B natural (also called B square) into a flat.
* enharmonic : obtained when the way of writing one or more notes of a chord is altered, although they continue to produce the same sounds . A practical example is writing G sharp as A flat which, leaving aside the particular judgments of some string players, should produce the same amount of vibrations, so that the ear cannot perceive a difference. Musically, the distance between two tonalities involved in this type of modulation is very large.
voice modulation
Finally, voice modulation refers to the alteration of tone with harmony and softness, that is, without it standing out in the listener's ears.
Announcers and actors must be trained to modulate their voice according to the genre they are in, without losing clarity of expression or elegance.