QTR-Quadtone RIP

What are some of the ways to get a neutral black or close to a neutral black?  What are the steps to go about it?

I want to use the standard Epson ink set for the R800 / R1800 which only has one Photo Blk (PK) and one Matte Blk (MK).  I want to use the QTR Curve Creator available for the PC and come up with one curve that is somewhat neutral (not the blending approach of cool, sepia, black, etc ...although I have obtained visually a pretty neutral looking black blend).

I have a scanner and X-Rite 810 densitometer that reads VIS (BW) and R, G, B values.  Also, I'm pretty familiar with using QTR Curve Creator.

I assume the process would apply to any printer / paper combination.

Thanks, Terry