"I'm super productive. I have a full album ready to go and it's much more pop," she said. "I'm calling it This Is Acting because they are songs I was writing for other people, so I didn't go in thinking 'this is something I would say'. It's more like play-acting. It's fun."
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Sia also said in the interview she put out 1000 Forms of Fear basically to get out of her publishing contract, because it demanded another solo release in the deal.
"I was planning to be a pop song writer for other artists," she said. "But my publishing deal was as an artist so I had to put one more album out. I didn't want to get famous so I kept all the songs I wanted and had a lot of fun making it."
The full interview comes out Wednesday in the NME.