I would suggest to try from this thread first, you need a microphone anyway and everything else in this guide is free. Then I would suggest using Thierry if you want to improve (see Roon & Home Audio Fidelity (Room Correction / convolution filter creation) ). You would then also use REW and USB microphone but instead of letting REW do the correction you let Thierry do them (he has very fancy software which fixes phase problems and crosstalk).
Having said that, give Dirac a try as well, they have a free 3 week trial. I also think they will release a new version soon, if they haven’t already.