Adam Levine worked at an American diner after his first record deal fell through.

The Maroon 5 frontman has opened up about his first foray into the working world and how after signing to a label very early on in his career, he had to took a job at Johnny Rockets when it ''fell through''.

After that the 'Sugar' hitmaker - who with his bandmates has sold over 20 million albums - decided to venture into working in television, before Maroon 5 became one of the world's best-selling artists and later landing his job as a coach on 'The Voice'.

Speaking to People's 'Voice Coaches on Blast' series, he said: ''Technically my first job was a musician because I got signed to a record label at a young age, so I did get paid for that.

''But then I got a job at Johnny Rockets when that record deal didn't work out, and then I got a job as a [production assistant] on a TV show actually.''

The 'She Will Be Loved' hitmaker also revealed his first concert experience was with his father, aged just 11.

He recalled: ''My dad took me to go see Warrant.

''I was 11. [It was the] Dirty Rotten Filthy Stinking Rich tour, and it was at the Santa Monica Civic Auditorium. It was crazy.''

Adam also spoke about his childhood and how his father handed him down the ''coolest'' first car, an '86 Chevy Blazer, which made him feel like ''the king of Los Angeles''.

He said: ''My first car I didn't buy.

''My first car was my dad's '86 Chevy Blazer which might as well have been a Rolls-Royce at that point because I thought it was the coolest car ever.

''I grew up in it, and it was black with a red stripe on the bottom. Badass. I literally thought I was the king of Los Angeles in my beat up '86 Chevy Blazer.''