The key to creating harmony in a room is to maintain balance. You create balance through scale, style, height and color. Another important factor is the creation of balance through lighting as well.
With the current trends of eclectic and transitional designs; creating balance and harmony is more important than ever.
When placing furniture in a room, be sure to evenly distribute the weight of the different pieces throughout the room. An example of this would be, to place a piano on the same side of the room as the sofa. To correct this and create a balance in the room, place either one opposite walls which will visually create balance and harmony in the room.