Trace Adkins, Brooks & Dunn, Miranda Lambert and Montgomery Gentry have been added to the list of performers at the Academy of Country Music Awards on May 18. Nominated for top vocal duo, Brooks & Dunn have won the most ACM Awards in history with 24 trophies. Lambert is up for top female vocalist, single ("Famous in a Small Town") and album (Crazy Ex-Girlfriend). Brooks & Dunn are also nominated for top country duo. Previously announced performers include Rodney Atkins, Dolly Parton, Sugarland, Taylor Swift and Carrie Underwood. The ACM Awards will air live from Las Vegas on CBS.