Beats Electronics LLC, a company co-founded by rapper/producer Dr. Dre that produces premium earphones and speakers, is getting a $500 million investment boost the from Carlyle Group, according to published reports.

The company behind the Beats by Dr. Dre brand confirmed the investment but would not provide the amount of money involved. In return, Carlyle reportedly will gain a minority stake in the Santa Monica-based company.

With backing from HTC Corp., Hewlett-Packard and Chrysler, Beats was launched in 2008 by Dre, whose real name is Andre Young, and co-founder Jimmy Iovine, chairman of Universal Music Group’s Interscope Geffen A&M Records unit. Beats is using a portion of the money to buy back a nearly 25 percent stake now held by HTC., the Taiwanese smartphone company.

According to a Wall Street Journal report, Beats had revenue of about $1 billion last year, up from less than $200 million in 2010, helped by earphones that run between $200 and $400. Market researchers at NPD group said Beats now has more than half the U.S. market for premium headphones.

Forbes lists Dre as the world’s third-highest paid hip hop artist ($40 million) behind No. 1 Diddy ($50 million) and No. 2 Jay Z ($43 million). Dre helped launch the careers of Snoop Dogg, Eminem, Xzibit, and 50 Cent, and he is also founder of Aftermath Entertainments.