Do you have a Dunn-Edwards' fandeck?
DE lists Munsell hue/value/chroma notations for the majority of their colors in the index of the fandeck.
Muslin - hue=6.45 Y value=8.0 chroma=0.6
Crisp Muslin - hue=1.60 Y value=8.6 chroma=0.7
They're not the same color.
Crisp Muslin is closer to the Yellow-Red hue family and has the potential to show peachy overtones (because it is *over* near the yellow-red hue family).
Muslin is closer to the green-yellow hue family; unlikely it would have any moments of peachy. Very likely it's going to look "neutral" once up in the space.
Crisp Muslin is slightly lighter than Muslin.
They're very, very close in terms of chroma (grayness). Like, so close it's almost not worth mentioning and I'm not convinced anybody could see the difference. However, according to the Dunn-Edwards' notation, according to the data, Muslin is more gray.
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Lights
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