I have run many an aes out from all kinds of equipment to the DR-680 with no adapters and never a problem.
mics: Soundfield ST450, JW mod Milab VIP-50's, Milab VM-44 Links (Matched Cards, Matched S-Cards), BR mod Nak 700's
pre's: Audio Developments AD 066(11), V2, Littlebox, Tinybox, Reutelhuber
pre/ad: Lavry AD11, Sony DMX-P01
recorders: Sonosax SX-R4, Tascam DR-680, Korg MR-1, Tascam DR-2, Mackie DL32R
playback: Teac UD-501 DAC, Meyer Sound