For The Listener, the solvers join together as one (4)
I believe the answer is:
unit
'one' is the definition.
(synonyms)
'for the listener the solvers join together' is the wordplay.
'for the listener' indicates a 'sounds like' (homophone) clue.
'the solvers' becomes 'you' (I've seen this in other clues).
'join together' becomes 'nit' (I can't justify this - if you can you should believe this answer much more).
'you' sounds like 'u'.
'u'+'nit'='UNIT'
'as' acts as a link.
Can you help me to learn more?
(Other definitions for unit that I've seen before include "Single manufactured item; military grouping" , "A single self-contained item" , "Single element; one" , "Single item, maybe part of a set" , "Piece of furniture" .)