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US rapper Timbaland, the executive producer on Xscape, says they were keenly aware of the need for the new Jackson record to stand up against the best that current pop music has to offer.

"How would I hear this on the radio against Katy Perry? Would it sound old, would it sound new?" asks the producer, who works closely with Justin Timberlake and Beyonce.

The album's producers include the Stargate collective behind Beyonce and Rihanna, and Rodney Jerkins, who has worked with the Black Eyed Peas and Lady Gaga.

A lot has indeed changed since Jackson's heyday.

Jackson died on June 25, 2009, from an overdose of the anesthetic propofol, administered by his doctor Conrad Murray to help Jackson fight insomnia as he prepared for his comeback. Murray was convicted of involuntary manslaughter in 2011.

A few months after his death, Sony and Jackson's lawyers signed a record deal - said to be worth more than $200 million by The Wall Street Journal - foreseeing the release of seven albums over 10 years.

The Jackson industry remains extremely lucrative: Forbes rated him as the highest-earning dead star last year. His heirs made $160 million last year, following $145 million in 2012 and $170 million in 2011.

But the producers of Xscape say that, above all, they want to live up to the high standards Jackson himself set. L.A.Reid, the head of Sony subsidiary Epic Records, says Jackson was a perfectionist.

"He said, 'I don't want another hit, I don't want to make just another record. I want to do something great. If it can't be great, if it can't be groundbreaking ... then we shouldn't do it," Reid says.

Critics have mostly been complimentary about the album before its May 13 release.

"While some of them are very obviously album tracks at best, there are flashes of genius that haven't been diluted or watered down. In fact, Xscape manages to bring most of them to life," says British daily The Guardian.