The seventeen-year locusts have descended on our town and their noise actually drowns out my daughter's music

Just a few things - you don't technically need the 'actually', it indicates a sarcastic tone and that your daughter's music is loud or annoying. The 'actually' is somewhat colloquial. Also, generally the more common phrase is "descended upon" rather than descended on. Lastly, unless the locusts are characterized by being 'seventeen-years' (as in, that's the exact, specific adjective that describes them), as opposed to 'seventeen year old', that's a strange/grammatically incorrect phrase. But if they're normally known as 'the seventeen-year locusts', you're fine!