I don't have any RTA gear, and I don't have the funds to acquire any in the near future, so what I've done in the past is use the published response curves for the cabs I'm using as a basis for setting up my 31-band EQ. I'd like to do the same with this rig, but I need some guidance to be able to get started.
First of all, for the DR200's... I found this chart, but what happens when I add a second cab? Is it a 3db increase? Also, does the shape of the curve flatten at all with two cabs instead of one? And what, if any, impact does the 16ohm driver have?

Next, the T39's... None of the published charts are specifically for a 20" T39 with the 3012LF. Has anyone measured one like that? If not, what's the best way to get (or extrapolate) the data?
Thanks in advance...