Dr. Dre is the biggest earner in hip-hop, thanks largely to his range of headphones and audio equipment.

According to Forbes magazine’s Cash Kings 2012 list, the rapper is thought to have earned $110 million before tax, in the last 12 months.

Last year, Dr. Dre, whose real name is Andre Young, and Jimmy Iovine, chairman and founder of Beats Electronics, sold a 51% share of the company to HTC for $309 million.

The star tops the earnings list, but has not released an album since 1999.

Throughout recent years the rapper has been thought to have been working on songs for forthcoming release Detox.

According to Forbes magazine's Cash Kings 2012 list, Dr. Dre is thought to have earned $110 million before tax, in the last 12 months

The project has been delayed several times and Dr. Dre himself has announced he will be working on his Beats products instead of new material.

Other artists in the list include Diddy, who makes cash from vodka and Jay-Z who has ventures including a restaurant, basketball team and cosmetics company.

Musicians further down the list like Nicki Minaj ($15.5 million) generate earnings from endorsements and advertising, rather than just from album and single sales.

The Forbes Top 10 Hip-Hop Earners 2012:

1. Dr. Dre – $110 million

2. Diddy – $45 million

3. Jay-Z – $38 million

4. Kanye West – $35 million

5. Lil Wayne – $27 million

6. Drake – $20.5 million

7. Birdman – $20 million

8. Nicki Minaj – $15.5 million

9. Eminem – $15 million

10. Ludacris – $12 million