What is Loud ?
Loud is (adj) 1. which is very easily heard Can’t you stop your watch making such a loud noise? Turn down the radio – it’s too loud. 2. (of colours) too bright He was wearing a particularly loud tie which didn’t go with his jacket at all. (adv) loudly I can’t sing any louder. She laughed out loud in church. (NOTE: louder – loudest)
source: Easier English, Student Dictionary Upper Intermediate Level