A row between neighbours over music being played resulted in one bashing a guitar over the other's head.
Sean Mooney and Claire Marley had words with Tyrone Ford at Spring Gardens supported accommodation in Knowle.
Bristol Crown Court heard Ford, who has ADHD and had not taken his medication, attacked them as well as police who turned up at the scene.
Ford, 20, now of no fixed address, pleaded guilty to assault occasioning actual bodily harm, assault and two assaults on emergency workers.
Judge James Patrick adjourned sentence until July 22 to allow social services to find Ford appropriate accommodation in the event of his release from custody.
Alex Daymond, prosecuting, described how trouble flared at Ford's flat after a problem over music.
Mr Daymond told the court: "He went to his bedroom and he got a guitar out.
"He struck Mr Mooney's head and he struck Miss Marley to her back.
"Mr Mooney was covered in blood from a three-inch to four-inch long gash.
"Mr Mooney got away from the situation, there was an argument between Miss Marley and the defendant and the defendant spat in her face and punched her to the jaw."
The court heard police were called and Ford punched PC Liam Parsons in the face and kicked and bit Special PC Benjamin Tucker.
Ford was arrested and taken to Keynsham police station.
He initially denied wrongdoing and couldn't recall assaulting the officers.
John Stokes, defending, said his client was a very complex individual and urged for the adjournment to explore the question of suitable accommodation for him.
