Remember that what we call "color" is a concensus thing. Most humans are sensitive to RGB, but the exact frequency and sensitivity of those R, G, and B components varies somewhat from person to person. There even seem to be some women who actually encode _four_ color sensing proteins instead of the usual three. We spend a lot of time learning to describe the various patterns of stimulus in our color sensors in terms of language. In effect, we are self-calibrating to an extent.
If you have a race with only one type of color sensor, then they'll have a completely different experience than we do with our multiple kinds of sensors. Same with only two sensors. More than that will just result in refinements of color (or possible extending into the IR and UV ranges) compared to humans.
Humans have a color response range that's just about the complement of green plants. That is, our maximum sensitivity just happens to be where plants reflect the most. Plants + Humans result in a use of the primary spectral output of our star. If your star is much dimmer and redder, your race is likely to see further in the infrared and less in the blue because that's where their star's output would peak. For a much bluer star, there would likely be enhanced UV response, but likely not a significantly different response in other colors.
If certain colors that the local race uses but that the humans couldn't see were designated as "danger" or "religion" or "sexual", then there is no end of hilarity that might ensue. A similar argument would apply to acoustic or chemical communications media.
EDIT: One thing that I neglected to mention is that although we are sensitive to three(ish) broad groups of frequencies and have panchromatic sensors for low-light conditions, what we describe as "color" is actually pretty variable. Our color sense is optimized for color constancy over a wide range of lighting conditions. If you have someone mix and paint the same "blue" under varying light conditions, they will look quite a bit different if placed side-by-side under bright light.
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