Credit: John Sciulli/; AKM Images Inc

Another day, another 'do!

After debuting a blonde pixie cut in October, Ashlee Simpson changed it up yet again when she dyed her hair platinum blonde on Thursday.

Who's behind Simpson's new 'do? The 26-year-old singer (and mom of Bronx, 2, her son with Fall Out Boy bassist Pete Wentz) visited the Andy LeCompte Salon in L.A. to get her lighter locks.

VOTE: Which hairstyle is best?

Simpson (who is a natural blonde) is quite the hair chameleon: since making her music debut in 2004, the "Pieces of Me" singer has sported black, brown and red shades at various times throughout her career.