The KWA 100SE is not a tube amp and thus does not have 'taps' for different impedances. The 100SE produces 100W into 8 ohms and will thus produce closer to 50W into 16 ohms, but will drive them without ANY trouble.
I have a pair of Zu Druids that are used to burn-in KWA 100SE amps and our other amps and they sound great.
Plenty of power and no issue with the impedance of 16 ohms.
Thanks,
Dan