In Shakespeare’s Cymbeline, Cloten uses lewd language to talk about Cymbeline. In an attempt to use musicians to court her, he calls on them to play ‘a wonderful sweet air’. The hark, hark!… line is chosen to represent sweetness and refinement, as a counterpoint to the previous crudities.
From Shakespeare’s Cymbeline, 1611:

CLOTEN: I would this music would come: I am advised to give
her music o’ mornings; they say it will penetrate.

[Enter Musicians]

Come on; tune: if you can penetrate her with your
fingering, so; we’ll try with tongue too: if none
will do, let her remain; but I’ll never give o’er.
First, a very excellent good-conceited thing;
after, a wonderful sweet air, with admirable rich
words to it: and then let her consider.

[Song]

Hark, hark! the lark at heaven’s gate sings,
And Phoebus ‘gins arise,
His steeds to water at those springs
On chaliced flowers that lies;
And winking Mary-buds begin
To ope their golden eyes:
With every thing that pretty is,
My lady sweet, arise:
Arise, arise.