Hi Ty.Someone may have made a comment about PI DJ speakers but many models of Pi's use professional (read DJ) components. This means you need very little power to make a lot of sound, then to top it off you can put a lot of power into them (translation - you can make yourself deaf or fill a big room :-) ).
What you might want to do is check the "price list" and click a few links. You will notice that some speakers are rated at 1000 watts. What you can't appreciate until you hear them is that one watt will fill most rooms in your house at what is considered "loud" levels. Many of Waynes designs use "horns" which are more efficient than other speaker designs. They can also be used to fill big rooms.
Note that the price list shows Complete price and kit price. Most people that don't live close to Wayne order the pieces and buy the wood to make the cabinets themselves instead of paying high shipping costs.
I hope this helps.
Grant.