Can confirm Creative E5 has a USB host port, where you can plug an apple Lightning cable into the iPad/iPhone and directly into the E5 without a CCK.
THE E5 sounds pretty great on it's own. My AKG K612 requires higher gain than a 600 ohm DT880, but sounds great on the E5 two "boxes" of volume from max on low-gain, more lively (less negative feedback) in high-gain mode where the E5 can be set to about 50% power.
Bonus, the E5 has an analogue line-out port to use the E5 DAC with another amp (like my tube amp), and the line-out doubles as a mini Toslink optical output (with included cable) if I wanted to connect to another DAC like my Bifrost Über.
I also have an Apple TV, sounds pretty good with optical out to a DAC + Amp.