The Core i7-2600K CPU will get in you in the door, for sure… But really, it’s single core speed would be the achilles hell by todays standards - particularly if you’re using Komplete suite and loading up single tracks with multiple plugins.
That said, The oldest machine i have is an i7-4790 and it ain’t too different to the 2600k and that can run things fine. The main thing is that your 2600k has AVX support, so if you get the new version of Massive as part of the Komplete suite it will run (Requires AVX support on the CPU).
If you haven’t got an SSD installed, i would invest in one, as that will provide a big difference on older machines. Plus they’re such a good price nowadays.
One other thing, live audio being recorded into a DAW takes less resources/CPU power than MIDI controlled VST Instruments such as Komplete. But luckily it’s easy to convert VST instruments into audio tracks should you need to recover CPU overhead.