Using modulations in music, temporary or definite, lends a sense of sophistication and brings freshness to your music. That said, this technique is something you should develop; the ability to modulate to any key; being able to come and go as you please while you navigate through the different tonalities; and doing so as smoothly as possible – or abruptly, if that serves your musical intents.

As seen, every chord can be redefined in terms of functionality. This means that a tonic chord can become a subdominant or a dominant from another key center – i.e. C major chord as the tonic, is also a subdominant in the key of G major or a dominant in the key of F major.

This is even more the case with altered dominants or diminished chords that have a particularly strong tendency for multiple functionality since their respective tensions seek resolution to different tonalities, making them excellent resources for modulation – see dominant chord substitutions.

Also, using other devices such as working with cycle chord progression, parallel harmonic movement or making use of the inherent functionality of chromatic mediant chords will offer great modulation potential and capability.

Mind you that a tonicization consists in the emphasis or confirmation of a new tonic in a given key. However, this process, unlike a modulation, tends to be brief and does not require a cadence in the new key. On the other hand, a modulation, to be considered as such, has to incorporate at least one cadence in the new key.

With that said, next we will be looking at the various ways of going from one key to another – see modulation:

Direct Modulation, also commonly referred to as phrase modulation – this is probably the simplest and most dramatic way of modulating since it occurs when a chord in the previous key is followed directly by a chord in the new key without any harmonic or melodic preparation:

Common Tone Modulation – considering the last chord of the cadence before the modulation, one of the pitches contained in this chord is sustained or repeated, while all the other notes of that chord change to the chord of the new key. This means that that the sustained pitch also belongs to the new chord/key and thus the name common tone modulation:

Enharmonic Modulation – similar to common tone, an enharmonic modulation occurs when the sustained pitch belongs to the new key but because of the tonal context it changes its name – i.e. F# becomes a Gb:

Pivot chord – the smoothest way to modulate from one key to another is to use a pivot chord. It consists in using one or more chords that are common to both keys – also see augmented sixth and secondary dominant chords :

Using Cm as a pivot chord between Ab tonality, as a iii degree; and Bb as a ii degree

Altered Common Tone Modulation – usually used to modulate to distant keys where no common chords exist. It consists in using a chord that has the same root in the target key center, proceed to its chromatic alteration by transforming the chord in a way that it fits into the new key, and then use the resulting chord as a pivot chord in order to proceed to the modulation– i.e. modulating from C major to Db major only has the pitches F and C in common:

Transforming the F major7 chord from C major tonality into an Fm7 and modulating to Gb Lydian from Db major – a iii – IV; while maintaining F and C as the common chord tones between tonalities

Another example of chord transformation modulating to Bbm while maintaining the colored common tones

Chromatic Modulation – it occurs when the voices of the previous chord move chromatically to the new chord from the new key. It is common to use secondary dominants for this effect as these contain chromatic tones from the previous tonality and will resolve chromatically to the chord in the new key:

Using Bb7 as a secondary dominant, introducing the chromaticism in C major tonality

A chromatic modulation is also considered as such when an altered chord is used to lead the transition to the new key:

Parallel Modulation – it is when you change mode without changing the root, like going from C Lydian to C Dorian:

Sequential Modulation,also known as Rosalia – it is when a phrase or chord progression is transposed diatonic or chromatically to a different key:

Chain Modulation – it consists in using a sequence of chord based on an interval cycle in order to quickly move through different keys until the desired key is reached:

Moving in minor thirds cycle chord progression to modulate to C maj – also see back cycling