QTR-Quadtone RIP

Below are some readings with K7 inks on a couple of papers. I just copied the last three lines of the QTR profile output.  Nothing systematic or comprehensive.  

The last time I bought Epson paper, I was amazed they have: 

Epson Ultra Premium Presentation Paper Matte - a flat matte surface on a bright white non-glare paper.  Yields highly saturated images, while maintaining excellent highlight and shadow detail.  Available in sheets, rolls and posterboard.  Formerly Enhanced Matte.
10.3mil - 192gsm - 104  ISO Brightness - 94% Opacity - matte finish - pigment or DuraBrite ink
 
Epson Premium Presentation Paper Matte - a heavyweight, bright white ultra-smooth finish for long lasting non-glare photos.  This paper is also great for craft projects, signage and black-and-white photos.     Formerly Matte Paper Heavyweight
9.0mil - 167gsm - 97  ISO Brightness - 94% Opacity - matte finish - pigment or dye ink
 
Epson Presentation Paper Matte - bright white coated paper for newsletters, flyers and reports.  Formerly Photo Quality Inkjet Paper
4.9mil - 102gsm - 90  ISO Brightness - 90% Opacity - matte finish - pigment or dye ink

I thought your problem might be Ultra versus just regular ol' Premium, but the measurements I got with the Ultra aren't much different than your 1.53.

In all fairness, the blacks on the Ultra Premium don't look that weak. I was surprised that the numbers were as low as they were.

Measurements taken with an Eye-One.

H. Photo Rag:

90.00	1.404	23.50	0.36	-0.59	-             L            b  |a                            +
95.00	1.545	19.45	0.53	-0.30	-          L                b | a                           +
100.00	1.709	15.23	0.27	0.22	-        L                    ba                            +

H. Museum Etching:

96.00	1.448	22.19	0.28	-0.01	-            L               b|a                            +
98.00	1.513	20.32	0.48	0.24	-           L                 ba                            +
100.00	1.691	15.69	0.44	0.74	-        L                    |ab                           +

 The Museum etching that I have bleeds severely at this level of black.

Epson Ultra Premium Presentation Matte:

96.00	1.547	19.37	0.94	1.93	-          L                  |  a   b                      +
98.00	1.562	18.99	0.85	1.82	-          L                  |  a   b                      +
100.00	1.567	18.84	0.99	1.65	-          L                  |  a  b     


Hope that helps.
ccolbertbw