Breaking silence, Adele's voice returns on television Fri Feb 10, 2012 10:26am EST (Reuters) - The post-surgery voice of British singer Adele was heard by U.S. television audiences on Friday as she sang an impressive a cappella version of her hit song, "Rolling In The Deep." The 23-year-old musician, who has not sung in public since vocal cord surgery, sang three verses of the hit in an excerpt of an upcoming "60 Minutes" profile that was shown on the "CBS This Morning" program. Her voice appeared back to its rich, soulful best. Since her throat surgery late last year, the public and the struggling music industry has been eager to know if the voice of 2011's top performer, whose popularity crosses all age boundaries, has fully recovered. The full "60 Minutes" profile will be shown before Adele makes her live comeback at the Grammy Awards on Sunday. She has six nominations, including album and song of the year. Reporter Anderson Cooper said she had to sing a cappella due to her nails being too long to play piano. She has told "60 Minutes" she first realized there was something wrong with her voice when was singing live on a French radio station and, "It felt like something popped in my throat." The singer had laser surgery to remove a hemorrhaged polyp on her vocal cords last November and was placed on strict vocal rest. She said the surgery was a wake-up call to help her realize her vocal limits. Reporting By Christine Kearney; editing by Patricia Reaney