This technique is used to explore contrasts between different modes that share the same tonic root of a given chord. It can be used more freely if the used chord is ambiguous enough to allow the implication of several modes throughout a given musical passage. That said, the chord quality will determine which modes or scales can be used over it – see matching scales to chords.
For instance, if you consider a Cmaj7 chord you can use the C Ionian, C major pentatonic or the C Lydian mode. Whereas if you choose an C5 chord, the possibilities increase immensely. Not only the previous scales can be used, but also C Aeolian, C minor pentatonic, C harmonic or melodic, C Dorian, and the list goes on. As long as the interval structure of the modes or scales coincide with the ones on the chord formation, those will be good candidates to use in a modal mixture context:
Going through C Phrygian to C minor harmonic and C lydian every two bars over a C5 chord
Nevertheless, it is not mandatory to first decide which chord you want to use and then explore the different modes that can go with it, nor a composer is obliged to stay in that chord permanently. Other chords may be introduced, in a context of modal harmony, to provide color and variety.
In sum, it is possible to go through different modes by using the same tonic root chord, but making sure that the used chord structure is reflected in the respective mode, and vice-versa.
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