Following the Gunners, some spectators sound rough! (4)
I believe the answer is:
rasp
'sound rough' is the definition.
(I've seen this in another clue)
'following the gunners some spectators' is the wordplay.
'following' means one lot of letters go next to another.
'the gunners' becomes 'RA' (Royal Artillery).
'some spectators' becomes 'sp' (I can't explain this - if you can you should give a lot more credence to this answer).
'ra' next to 'sp' is 'RASP'.
Can you help me to learn more?
(Other definitions for rasp that I've seen before include "fruit" , "Coarse file or grating sound" , "sort of berry?" , "Abrade" , "Grate; scrape" .)