Artist's dire channel (6)
I believe the answer is:
strait
'channel' is the definition.
(I know that strait is a type of channel)
'artist's dire' is the wordplay.
'dire' is an anagram indicator.
'artist' with letters rearranged gives 'STRAIT'.
(Other definitions for strait that I've seen before include "Narrow passage joining two large areas of water" , "-- -laced (prudish)" , "Narrow sort of traits (6)" , "Connecting passage of water" , "Narrow stretch of water for artist" .)