Instrument old character used to accompany Jolson? (7)
I believe the answer is:
althorn
'instrument old' is the definition.
'althorn' can be an answer for 'instrument' (I've seen this before). I am unsure of the 'old' bit.
'character used to accompany jolson?' is the wordplay.
I cannot really understand how this works, but
'character' could be 'thorn' (thorn is a kind of character) and 'thorn' is present in the answer.
'jolson?' could be 'al' (singer Al Jolson) and 'al' is found in the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for althorn that I've seen before include "musical instrument" , "one of the brass" .)