Warm up those vocal cords, Baltimore. The NBC singing competition &quot;The Voice&quot; will hold open call auditions on Saturday at the Baltimore Convention Center.&quot;The Voice&quot; has split the day into three groups — 7 a.m., noon and 4 p.m. As of Friday morning, the 7 a.m. and 4 p.m. groups are full, while the noon group is still available for registration.Those interested must be at least 13 years old by March 24. The registration process can be completed at nbcthevoice.com.Entrants should enter the convention center's Charles Street lobby. The convention center is located at 1 W. Pratt St.Last year, Randallstown singer Joe Maye, whose coach was Blake Shelton, was eliminated during the first live playoff results show. Season 12 of &quot;The Voice&quot; premieres at 8 p.m. Monday on NBC.