Vital panel required to make instrument (8)
I believe the answer is:
keyboard
'instrument' is the definition.
(I have seen 'Musical instrument' mean 'keyboard' so perhaps 'instrument' could also mean 'keyboard')
'vital panel required' is the wordplay.
'vital' becomes 'key' (key can mean important).
'panel' becomes 'board' (synonyms).
'required' is a charade indicator (letters next to each other).
'key'+'board'='KEYBOARD'
'to make' is the link.
(Other definitions for keyboard that I've seen before include "It can produce notes" , "Component of piano" , "(Part of) musical instrument" , "Piano or computer device" , "There are various characters on this" .)