Neidlinger was born in Westport, Connecticut. After Yale University, he moved to New York City and began playing in various jazz settings. He joined Cecil Taylor's group in 1955, played with Herbie Nichols and recorded extensively with Taylor's groups with Steve Lacy and with Archie Shepp among others until 1961. He was also involved with new directions in classical music (John Cage, Mauricio Kagel, George Crumb) and Gunther Schuller' s Third Stream music.
He has worked extensively as an orchestral and as a session bassist before becoming a musical educator at the New England Conservatory and CalTech. Together with Marty Krystall he founded K2B2 Records.