Sorry about the loss, my friends. I didn't know him, but knew the name. I'll get it up on CEPro.com. Stanley, do you mind if I use your words in your original post? Here is his bio on Wisdom Audio:

David Graebener
Executive Vice President
David has been involved with the design and development of transducers and systems for more than 30 years and is an authority on planar-magnetic design. David began his audio career in the late 1970s as co-founder of Speakerlab, a Seattle-based loudspeaker design and manufacturing company. As a pioneer in the development and application of planar-magnetic transducers, David joined Tom Bohlender to found the Bohlender-Graebener company in the early 1990s. David has been sought after as a consultant for transducer development, with a focus on planar-magnetic applications. David is owner of Advanced Transducer Engineering and co-founder of Solution Matrix and has completed design work for Boeing, American Technology Corporation, NCT, Pacific Car and Foundry, Carver, Toshiba, Onkyo and Eastern Asia Technology Company. David has been involved in the authoring of several patents granted or pending related to planar-magnetic transducer design and is associated with the development of more than 130 electro-acoustic designs.