It has AAC but this is a bit of a step down from LDAC (at least technically - we can argue all day about what can and can't be heard, of course).I think it's AAC? Someone who knows more about BT can confirm, I don't have a clue
BTR7 codec capabilities are AAC/SBC/aptX/aptX LL/aptX adaptive/aptX HD/LDAC
(source - Fiio website)