I have actually read all the posts in this thread. It was posted three years ago, but poeple are reading this, and it is clear that help is need to match colours. First you need to know a few basics things about colours:
1. The most common colour configurations in home decor consist of either complementing harmonies or contrasting harmonies.
2. Colours are graded according to its hue and saturation levels to determine wether it is a warmer or cooler colour. Decorators love the idea of playing with warmer colours in winter, and then change to cooler colours in winter.
3. A colour might match perfectly and you can still not like it. So, choose a colour that works for both you and your decor.
Ok, here we go... I will refer to the colour names as listed in the wikipedia colour list:
en.wikipedia.org
Tiggersmom commented that Mocha is a good colour to go with, combined with shades of cream. Excellent, safe choice. Mocha on the walls create a warmer atmosphere to the room (it's a warm, complementary colour for a dark brown base colour). Cream is a high contrast, cooler colour, and also a compliment harmony for Mocha. It might be a little monochromatic for the individual who is looking for the wow!
Rungirlrun suggests earthy green and lighter blues. Both great colour choices if you aim to create a cooler atmosphere. Be carefull when you move out of the monochromatic harmonies. Green and blue can have millions of shades and tones which will not macth. I suggest "Olive drab" or "Sea Green" as cooler green complements for chocolate brown. For blue I recommend "Columbia Blue" or "Baby Blue", Both are cooler, high contrast colours.
I appreciate
Marty's suggestion. I would do the same. There is a risk in trying to match the wall colour to the exact colour of your couch. If you don't get it 100% correct people will notice your failed attempt. If you want to go with a dark and warm complementary colour that will match the couch I would suggest "Camel". For a high contrast warm colour I recommend "Burgundy", "Burnt Orange / Sinopia".
I can picture
Sunnyd's idea. I like it. Combining the warm mocha with the cooler Magnolia. If Magnolia is too "White" for your taste you can replace it with "Beige" or "Pearl" (slightly warmer).
PB4813 mentioned Caramel. I would be very careful. PB4813 also mentioned that they have a deep wine colour couch. Caramel will work for that configuration, but the red tones in Caramel will be accentuated against the dark chocolate couch and look a bit off. If this is what you are looking for I also recommend that you compare the warm compliments of "Copper" and "Dark Corral".
Paintgirl1 wants to try a Warm Grey. You get two types of Grey. Achromatic greys have no hue, and I recommend staying away from these (when you add black paint to white paint until you get the desired grey). If you want to go grey I recommend Chromatic greys that contain hue. For the chocolate brown couch I recommend "Xanadu" or "Taupe" for a dark warm atmosphere.
Some other colours not mentioned in this thread that will go well with Chocolate brown couches:
Complimentary / Cool:
"Duke Blue" - A very deep, dark blue.
Contrast / Warm:
"Old Gold" - I know it might be "bling", but gold still looks great with a dark chocolate couch.
Contrast / Cool:
Violet tones like "Lavender blush", "Mauve", "Thistle", and "Whisteria". I love "Whisteria", It will look great with dark brown if you are looking for a violet / purple tone.
I hope this helped a bit to answer a few colour questions about the chocolate couch.