Founded by renowned tube expert Aspen Pittman, Groove Tubes began by manufacturing tubes for use in guitar amps. Once established, the company expanded into the design and creation of other tube-based gear, including microphones and studio electronics.
The microphone product line was at one time sold to Alesis and then Fender. As of 2012, Fender retains the IP for the Groove Tubes microphones.
See also Sterling Audio, a new microphone company that sells microphones that leverage Pittman’s designs.