headphones 600 ohm with Konnekt 6 works??

Headphones 600 ohm with Konnekt 6 works??

Or do I need an headphone amplifier also?
I have Sennheiser HD 540 reference I. the first one and the are 600 OHM. I use it for mixing and i would like to know that the sound is 100% to my ears! = )

Thanks!