I have been urged by earnest violins
And drunk their mellow sorrows to the slake
Of all my sorrows and my thirsting sins.
My heart has beaten for a brave drum's sake.
Huge chords have wrought me mighty: I have hurled
Thuds of gods' thunder. And with old winds pondered
Over the curse of this chaotic world,-
This is less likely to be a reference to the Great War and military drums, but an assertion by the poet that he was ‘brave’ in love, perhaps having the courage to pursue a woman or man whom he feared might be unobtainable. At the time homosexuality proked revulsion and censure. 
 Note the pace of this line, with the elongated vowels and monosyllabic ‘brave drum’s sake’. The slow, deliberate, rhythmic tread conveys its importance. This works well when the poem is red aloud. 
 The rhythm of this first section is noticeably varied and expressive, appropriate for a poem about music. This little sonnet could well be the lyric of a song.