Well, in terms of figuring out how much compensation to apply, and where, I’ll use a combination of measurements on other rigs, using well-known reference headphones, and figure out something reasonable from there.
After which it’ll just be a case of creating the appropriate compensation file, which once you know what you want is simply down to editing values in a text file. These can be retroactively applied in REW.
Now, this won’t be perfect, but as long as the peak is consistent enough it should give a better correlation to other measurement systems. Though at some point I will probably bite the bullet and invest in a more serious, reference, measurement head and “ear” simulators.
As it stands, I have another rig of my own build - but I figured using the miniDSP EARs for now would at least offer something that stands a chance of resulting in measurements that have some correlation to something easily available to others.