The use of leitmotif was one of the most important devices used in conveying emotion. This device is fully utilised in the Gershwin’s folk opera musical, ‘Porgy and Bess’. Porgy’s leitmotif is an upwards grace note which symbolises his stumbling due to being a cripple and features a perfect 5th followed by a minor third which shows the solidity and folk like nature he shares with Catfish Row. He sings ‘When Gawd Made a Cripple’ to demonstrate his loneliness, and the material from this number is reprised and played when he provides shelter for Bess showing their emotional connection.
‘Lonely Room’ from ‘Oklahoma!’ is sung by Judd, the villain of the production. It is the only song in a minor key reflecting his dark feelings of loneliness; however, his fluctuating emotions are illustrated by the changing patterns of the vocal melody; the start is recitative-like, using a limited range of notes, but after he sings, ‘And I'm better ‘n that smart aleck cowhand’, the melody breaks out of this and moves freely to dramatically higher notes, showing his intentions to liberate himself from his circumstances. Jud’s final note is a C sharp, forming a dischord with B minor which shows his emotions are still dark.
‘Carousel’ was produced two years after ‘Oklahoma!’ and had almost the exact same production team. Its number, ‘If I Loved You’ is a duet in which the lovers Julie and Billy sing, never at the same time, but the same musical material to show that they both love each other but are reluctant to express their emotions. The lyrics show the couple’s insecurities as the line, ‘Soon you’d leave me’ is supported by a Db minor chord. The strong modulation to Bb minor expresses their strong feelings toward one another and during the reprise of this song; this is the section in which Billy begins to sing after the orchestra played the first phrases to enhance the impact of Billy’s initial entry. Hammerstein changes the lyrics here to show that Billy is now able to express his love for Julie from, ‘if I loved you’ to ‘how I loved you’.
In the musical ‘Wicked’, Elphaba realises that is she is not wanted by her parents or Fiyero in the song ‘I’m Not That Girl’. The simple, delicate accompaniment symbolise her delicate and fragile emotional state while the 6/4 bars places within the 4/4 metre gives her extra time to process her painful emotions. The diatonic A section creates the effect of a simple and direct emotional expression, while the B section which is more chromatic reflects her wish to escape into a less painful fantasy. However, the final chord which is an inversion of the dominant accompanied by a low note in the melody show that, as far as Elphaba’s emotions are concerned; the story is not finished yet.
In contrast, ‘Oh, I Can’t Sit Down’ from ‘Porgy and Bess’ portrays emotions of high spirits as a crowd prepare to go to a church picnic on Kittiwah Island. This excitement is portrayed through the opening fanfare sequence with a syncopated motif presented antiphonally between low and high brass and percussion and fast, swirling strings and xylophone. The unison vocal writing maintains a sense of shared excitement.
In summation, it was not just the plot and script that allowed the audience to gain insight into how characters were feeling; music supported this and enhanced their emotions, allowing them to be communicated more easily and effectively.