In the 1980s, he established River North Records. At the time it was the largest full service audio recording facility in Chicago.[citation needed] By 1991 Thomas was running River North Recorders as well as Platinum Entertainment, a subsidiary of PolyGram. As president of Platinum, Thomas recorded and/or produced the Beach Boys, Peter Cetera, Willie Nelson, Toby Keith, and Alan Parsons, among others.[citation needed] Platinum Entertainment went public in 1997.[citation needed]

Thomas left Platinum in early 1997 and began producing and co-writing Brian Wilson's Imagination for Giant Records. He also served as musical director, co-producer and promoter of Wilson's first world tour.[citation needed] In 1999, Wilson filed a suit against Thomas, seeking damages and a declaration which freed him to work on his next album without involvement from Thomas.[4] The suit was made after Thomas allegedly began to raise his industry profile and wrongfully enrich himself through his association with Wilson. Thomas reciprocated with a suit citing that Brian's wife and manager Melinda Ledbetter "schemed against and manipulated" him and Brian. The case was settled out of court.[5] According to AllMusic: "The live DVD productions that were eventually released after the partnership of Wilson and Thomas went south are apparently studied in some recording classes as examples of how performers can be edited out of a production, specifically Thomas and his frequent collaborator Steve Dahl."[3]

Thomas began working in video in 2000. Forming Kurtis HD Partners with veteran Chicago television journalist Bill Kurtis, Thomas produced high definition hard news documentaries for several networks, including A&E, PBS, and NBC. One year later, he co-founded the production company HD Ready, LLC.[citation needed]

In 2012, Thomas, along with John Branca and Tony Dimitriades, helped orchestrate the 50th Anniversary Reunion Tour of the Beach Boys.[citation needed] In the same year, Thomas co-wrote, recorded and mixed the Beach Boys' 29th studio album, That's Why God Made the Radio as well as directed and produced the hour-long television documentary The Beach Boys: Doin’ It Again.[citation needed] He returned to co-produce the Beach Boys' Live – The 50th Anniversary Tour, which was widely criticized for its autotuned vocals.[6][7] Thomas again co-produced Wilson's solo album No Pier Pressure (2015); in several reviews, Thomas' contributions were a significant object of criticism.[8][9][10][11][12] In 2015, Wilson denied using autotune in his work.[13]

Since Soundstage, Thomas has also directed and produced a string of new music concert specials airing on PBS called Front Row Center.