The original San Angelo chapter formed in 1955, but went inactive after a few years. The chapter was reactivated in 1970-71 and was named the Twin Mountain Tonesmen. After a couple of years, the chapter went inactive again until it was reactivated in 1979. Since that time, the chapter has had slow but steady growth and today has an active membership of approximately 30-40 men.
Beginning in the late 1980's, the chorus began winning Society-sponsored contests at both the Division level (West Texas area) and the Southwestern District level (Texas, Oklahoma, New Mexico, Arkansas, and Louisiana). As of 2001, the chorus has won the Division I contest numerous times, placed second in the new Southwest Division contest and has won the Southwestern District Small Chorus competition a record five times.