Leitmotifs form a large part of this piece. These are very short phrases which are associated with specific emotions, such as grief and desire. The Tristan progression is a special leitmotif because instead of portraying an emotion, it portrays a person, Tristan. In this leitmotif the Tristan chord plays a major part because the chord is dissonant and you think it must resolve but it doesn’t which makes it feel uncertain. The cello’s yawning opening falls, to form part of the Tristan chord. This chord is dissonant, and therefore must resolve. However, unlike a ‘normal’ chord, where part of the chord stays the same and part of it moves on, all parts move from the Tristan chord in an unorthodox chromatic elision. There is therefore a process associated with this chord, in which the harmonic function of each part is uncertain and therefore there is a constant harmonic ambiguity. This was normal in romantic times because the composers were a lot more adventurous than classical composers.
Similarly, Wagner experiments with the orchestration in the piece. Bars 4-7 are a repeat of bars 1-3 transposed up a minor third and with different orchestration. In bars 8-11 the Tristan chord is played ‘upside down’ with the diminished fifth in top and the perfect forth down below. Bars 12-13 are basically the same as bars 10-11 except that the orchestration is different with the flutes playing what the oboes played in bars 10-11 but an octave higher. The orchestra used in this piece is larger than a normal classical period orchestra with the extra trombones and two extra horns and with some percussion as well.
Wagner created the leitmotivs using thematic transformation which is a typical characteristic of romantic pieces. Thematic transformation is the reordering of pervious motifs to make a new one. The ‘love potion’ is mainly made of three different themes, seen in the glance and desire motifs. The first leitmotif is at the very beginning of the piece and is the grief motif. This tells the audience that the outcome of the opera will not be a happy one. Straight after this the Tristan chord is played in the woodwind with the oboes playing the desire motif. The same sequence appears in bar 10-11 however with a slightly different orchestration. The appoggiaturas in bar 17 add a little interest in the piece and just hold the cadence.
The structure is different from the normal form for a prelude with an exposition, then a middle section and then two recapitulations, happening at bar 25 and then again at bar 82. At the second recapitulation there are three different leitmotifs in place at the same time. This creates interest and slight dissonance.
The aspects which most relate the piece to romantic music are the leitmotifs, extensive use of dissonance, thematic transformation and the use of the tenor registry which we see at the very beginning of the piece.