I assume that you are using the 1070's multichannel analog input bass management in the "LPF/HPF" mode (analog crossovers), which takes care of the bass management but skips the 1070's channel trim and delay settings. In that case, you are doing the right thing by calibrating it.

I don't know of any SACD test discs, but you ought to be able to get pretty darn close using a standard DVD calibration disc like Digital Video Essentials, AVIA, or GetGray and playing it through the multichannel analog output.