Curtail performance of quiet tenor (7)
I believe the answer is:
shorten
'curtail performance' is the definition.
'shorten' can be an answer for 'curtail' (I've seen this before). I am not certain of the 'performance' bit.
'quiet tenor' is the wordplay.
I cannot really understand how this works, but
'quiet' could be 'sh' and 'sh' is found in the answer.
an anagram of 'tenor' is 'orten' which is present in the answer.
No letters remain.
This explanation may well be incorrect...
'of' acts as a link.
Can you help me to learn more?
(Other definitions for shorten that I've seen before include "Prune" , "Reduce in length" , "Curtail" , "Truncate" , "contract" .)