Sad colour and tone from jazz singer, expressively flattening third, for instance (4,4)

'jazz singer expressively flattening third for instance' is the definition.
I can't judge whether this defines the answer.

'sad colour and tone' is the wordplay.
'sad colour' becomes 'blue' (I've seen this before).
'and' means one lot of letters go next to another.
'tone' becomes 'note' (note is a kind of tone).
'blue'+'note'='BLUE NOTE'

'from' acts as a link.

Can you help me to learn more?