N.E.R.D.'s upcoming album 'Nothing' has been a long time in the making. Rewind to October when the release was still titled 'Instant Gratification,' and the experimental trio had just recruited Canadian singer Rhea to add some female vocals to the project. But now, Pharrell says that the foursome has been cut down to three again.

"Now you have this little Tinkerbell that's just stepped in and has been amazing," Pharrell originally said in October. "It's made it a fun process. We can go in so many more directions, because we have the vocal support."

But according to the N.E.R.D. frontman, the trio "experimented" with Rhea -- who has a background in classical music -- then decided to go their separate ways. "She needed her own band to do the kind of music that she does, which is R&B," Pharrell said. Despite the separation, Pharrell will still handle production on Rhea's upcoming album with her band, Jealous Lover.

The revamped N.E.R.D. album 'Nothing' is currently slated for a September 7 release. In April, Pharrell announced that he had scrapped 27 records from the album to start from scratch.