After attending Moravian College in Bethlehem, Pennsylvania, where he received a Bachelor of Arts degree, Somach worked at WYSP-FM as a radio announcer and programmer before launching his own independent production company, Denny Somach Productions (DSP). Among the syndicated and network radio programming produced by DSP are a number of successful programs, including The Classics, a widely syndicated weekly retrospective show that was originated in 1999 as The Rock of the century; Legends of Rock; Live From the Hard Rock Cafe and Rolling Stone Magazine's Continuous History of Rock and Roll.

Somach has been a consultant or director for several cable networks, including MTV, Cable Music Channel, the Comedy Channel and The Fine Living Network. He produced The News That Rocked '81, the first outside program broadcast on MTV. He was also a consultant for satellite radio XM RADIO and a contributor to Comcast Network.

Among his television production credits are Evening/PM Magazine; Solid Gold Rock 'n Roll the first 30-minute music infomercial; and Sixty Greatest Hits of the Sixties, the first long form record collection infomercial featuring a package developed by a major record label. The infomercials featured Wolfman Jack and Davy Jones, respectively. Somach has also produced records and videos for artists such as Johnny Winter, Todd Rundgren, Alan Parsons, and Barbara Mandrell. He served as executive producer for Eric Johnson's album Ah Via Musicom, featuring the Grammy award winning song "Cliffs of Dover".

In addition to producing, Somach has worked as a reporter on Friday Night Videos and a host on Hot Spots, a weekly concert series he developed for USA Network. He was a contributor to Solid Gold.

He has authored two books: Ticket to Ride (1989) and Meet the Beatles...Again (1995).