Thanks for all the replies. I'm actually now between a used c 658 or a fairly priced new minidsp shd studio. I'm leaning towards the later as it comes with the full license, and I can use the dac of my primare i35 prisma. The only thing holding me down is if this dirac thing is worth the 1000 euros this little piece of hardware costs. It's the only thing I can do for room correction as I can't treat the room as I am renting and don't want to mess with the walls.