Oki C5550 MFP User Manual page 210

If you are using a source CMYK document, use the following
printer driver settings to perform a CMYK Ink Simulation:
CMYK Simulation_oda.jpg
1. On the printer driver [Color] tab, select [Graphic Pro] (1)
and click [Options].
2. Select [ICC Profile Color Matching] (2).
3. Select the [CMYK Input profile] (3) that corresponds to
the device you are trying to match such as a SWOP or
Euroscale Press. If you have another CMYK Ink profile that
you wish to use, select it here as the appropriate "CMYK
Source x" profile.
Remember that the names "CMYK Source 1", "CMYK
Source 2" and so on relate to the number assigned to the
profile using Profile Assistant.
ICC profiles to the hard disk" on page 202.
Use the [Preserve Black] option to keep the original gray
component (K channel) information. If [Preserve Black] is
C5550 MFP User's Guide
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