Yongki considers himself as an aerospace engineer by day and an audio/home-theater enthusiast by night/weekend. He earned his doctoral degree in aerospace engineering from MIT in 1999 and has pursued a career in academia before changing path to join the aerospace industry. He has been writing for SECRETS since its early years, but was on hiatus during the few years when he was living overseas. He has been actively writing for SECRETS again not long after his return to the US in 2012. Although his field of expertise is in aerospace control systems as exemplified by more than 80 technical articles in various aerospace-related journals and conferences, his passion has always been in hi-fi audio reproduction. It is this continued passion for audio that has kept him as a long-time member of the SECRETS team.