Miso vs. Doenjang

Is there a big difference between Miso paste and Doenjang paste? I was at the store and grabbed the Miso paste, but the Doenjang paste was a bit cheaper, and since both were soybean pastes I bought it. I was planning to make Miso soup with some dashi stock, but now I can't make Miso soup since I don't have Miso. I was wondering, will the soup come out similar using Dashi and Doenjang?

http://en.wikipedia.org/wiki/Doenjang
http://en.wikipedia.org/wiki/Miso
Seems similar to me, except that the most common miso uses soy but not necessarily all do in my understanding. Granted, I didn't read the whole articles.

same thing but...

Miso is (usually) blended better (no discernable pieces of soybean), and is fermented longer