Jkphoto is brief and very much to the point, IMHO. But "the room" is ambiguous: does it include acoustic treatment or not? If the room "measures up" half-decently, in that its main resonant modes (its three main dimensions) aren't too close together, acoustic treatment can make the difference between great sound and really annoying and fatiguing sound. See F. Alton Everest's books, "Master Handbook of Acoustics" 4th edition and "Sound Studio Construction on a Budget", and I've heard Robert Harley's book is good on this too. If you can do any DIY, acoustic treatment is a LOT cheaper than a fancier pair of speakers, and does at least as much good. I have designs for Argent Room Lens clones and RPG-style diffusors, if you're interested in taking the DIY route.
