@jkbtn Ted keeps the precise mechanism of the FEQ close to his chest but there's a discussion of the impact these systems have, and also how well they work with other tech in these two reviews
http://www.soundstageultra.com/index.php/equipment-menu/476-synergistic-research-high-frequency-tran...
http://www.6moons.com/audioreviews2/synergistic/4.html
http://www.soundstageultra.com/index.php/equipment-menu/476-synergistic-research-high-frequency-tran...
http://www.6moons.com/audioreviews2/synergistic/4.html