It is beautifully done, though I feel it is important to point out (apologies if others have already done so - with 48 comments the Medium interface makes it almost impossible to view them all properly) that those sounds are ultimately the work of the translator, Robert Vilain.
As Rilke was primarily a poet, his prose is naturally poetical, which adds an extra challenge to the task of translation - the words have to not only be right, but feel and sound right in mouth and ear.
I've just looked up the original passage, which is this:
Irgendwo klirrt eine Scheibe herunter, ich höre
ihre großen Scherben lachen, die kleinen Splitter
kichern.
The splinters, for example, are just 'small', but Vilain has made them 'smaller' to maintain the trochaic rhythm of the two syllables. He could have gone for 'little splinters', but that would perhaps have overheightened the sense of 'silliness', when combined with the 'giggling', as 'little' in English implies more than just a dimensional description.
I can scarcely imagine the effort required to process all 100,000 words or so, lending to each the detailed care they demand.
In case anyone is interested, I wrote a brief piece recently touching on the business of translating poetry:
https://medium.com/ellemeno/lorcas-la-monja-gitana-retranslated-255c727f9f4d
Thanks for this article, Michelle. It's always fascinating to see what other people are reading, and how it speaks to them as writers.