Epson R3000 printhead (?) issues

[pharmacist]

I found my Epson XP-15000 produces excellent monochrome output (even using my own brewed ink mix using 15% PK with clear ink base to produce the grey ink). But is the print on the ET-8550 done using the ABW-mode ?

 

[Ink stained Fingers]

I'm wondering that the XP-15000 and the ET-8550 would print visibly different - both use CMYK +1 gray dye inks - no light inks - the XP-15000 with an additional red and the ET-8550 with an additional matte black. Only a direct comparison under the same conditions - paper - driver settings - could answer that question. Both use a 6 color printhead with 1.5 pl min droplet size. I could help out with prints on a ET-8550 - with Epson 106 inks