One crowd that's bound to listen? (7,8)

'bound to listen?' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.

'one crowd that's' is the wordplay.
I cannot quite understand how this works, but
'one' could be 'i' (Roman numeral) and 'i' is found in the answer.
'crowd' could be 'd' and 'd' is found within the answer.
'that's' could be 'ie' and 'ie' is located in the answer.
This may be the basis of clue (or it may be nonsense).

Can you help me to learn more?