Johnny Depp. Photo by Jordan Strauss/Invision/AP

Johnny Depp insists his use of a sound engineer and earpiece helped bring a "truth" to his acting because he gets fed sounds that help him respond with just his eyes.

The 'Pirates of the Caribbean' actor's former management company, The Management Group (TMG), accused the star of never learning his scripts, and alleged he has spent "years" paying sound engineers to feed him his dialogue on set instead in court documents filed last year, and now Johnny has responded to the claims.

Though he didn't confirm if his lines were fed to him by the staff member, he admitted to having the earpiece, through which various sounds were played to help him act with just his eyes.

He explained: "I've got bagpipes, a baby crying and bombs going off. It creates a truth. Some of my biggest heroes were in silent film.

"It had to be behind the eyes. And my feeling is, that if there's no truth behind the eyes, doesn't matter what the f***ing words are."

The legal documents, written by attorney Michael Kump on behalf of TMG's Joel and RobertMandel - who are countersuing the actor in response to his lawsuit against them for mismanaging his money - stated: "Depp insisted that this sound engineer be kept on yearly retainer so that he no longer had to memorise his lines."

TMG have maintained Johnny's financial woes are due to his out-of-control spending but the 54-year-old star branded some of their claims of his extravagance "insulting" - because he spent much more.

In a tell-all interview with Rolling Stone magazine, he said of the claims he spent $30,000 a month on wine: "It's insulting to say that I spent $30,000 on wine. Because it was far more."

And he insisted they were wrong in how much it cost to shoot the ashes of his late friend Hunter S. Thompson out of a firework, explaining the bill was higher because he wanted the arc of the rocket to be higher than the Statue of Liberty.

He said: "By the way, it was not $3 million to shoot Hunter into the f***ing sky. It was $5 million."

The 'Dark Shadows' actor originally sued TMG for fraud, while they hit back with a countersuit in which they insisted his financial situation is his own doing.