[3] Thomas began making a name for himself on the concert circuit and in 1937 became the youngest singer and only Welshman to have won the Metropolitan Opera's annual radio auditions.
The revised version premiered in concert form at Carnegie Hall on 21 February 1941 with excellent reviews for Thomas who "revealed a fresh and voluminous voice".
[9] After the performances ended, Damrosch wrote to Thomas: With your exquisite voice which you owe to your Welsh ancestors, and with your great artistry, you had already achieved a commanding position on the concert stage – but in your portrayal of 'Cyrano' you have developed so fine a perception of the requirements of opera, that that career is also open to you if ever you choose to undertake it.
At its height, Thomas sang 60 live concerts a year in the United States and further afield in Canada, Wales, England, Germany, and Australia as well as performing on weekly radio broadcasts.
[4] In 1948 and 1949 he hosted the weekly radio show, Your Song and Mine, produced by Frank and Anne Hummert and starred on their Manhattan Merry-Go-Round in its final years.
In the ensuing years, he cut back his concert schedule and concentrated on informal lecture-recitals as well as teaching in Arizona colleges and in his private voice studio.