Mr and Mrs Clark and Percy (1970-71)

https://www.tate.org.uk/art/artworks/hockney-mr-and-mrs-clark-and-percy-t01269

https://www.riseart.com/guide/1780/5-things-you-didn-t-know-about-david-hockney#:~:text=SYNESTHESIA,in%20response%20to%20musical%20stimuli.