Ah but you do by using HouseCurve: Room correction using your iPhone and HouseCurve
If you have an iPhone (or can borrow one to set up HouseCurve) and would like try using dirac with Roon then HouseCurve is a nice, inexpensive way see if dirac will work on your system. Then if you like the results you can always invest in a more robust digital room correction setup. HouseCurve is easy to use and not a big investment and the results are totally reversible since HouseCurve basically generates a specific convolution filter for your room.
That’s not surprising since Dan Clark tunes all his headphones using the Harmon Curve. The Stealth almost exactly matches the Harmon Curve.