Oh please! Bose is overpriced crap. pucman has absolutely no idea what he / she / it is talking about and should not be answering questions in this category. Anyone who knows anything about high fidelity or pro audio knows that Bose is geared towards gullible people and wives who don't want to look at speakers larger than a soup can in their living room.
What you need are a pair of speakers. Not one. Music has been in two channel stereo sound since the late 1950s. Lets not backslide here. It will also enable you to position them so between the two, all parts of the room have a speaker directly pointed at it. Reflected sound is distorted sound. Look how modern concert sound system speakers are set up.
You wantr pro or semi pro sound type speakers - active ones. Portable in the sense that they are not huge and can take the knocks. Something with an eight inch woofer should fit the bill being small enough to easily move around and still large enough to sound descent with some bottom end and not distort when loud.
Behringer is budget prop sound stuff. JBL Is pricer but worth it. There are many other brands as well/ KRK makes some very good active speakers. They may well be your best bet.
Here are some links:
http://www.sweetwater.com/store/detail/CE500ABK
http://www.sweetwater.com/store/detail/B108D
http://www.sweetwater.com/store/detail/LSR308?adpos=1o4&creative=54989476081&device=c&matchtype=&network=g&gclid=Cj0KEQjw04qvBRC6vfKG2Pi0_8gBEiQAAJq0vc_vXBrDH7liUyH-Jxr0eZ4XGJGq-oOg-Hjy5La86RwaApkg8P8HAQ
http://www.sweetwater.com/store/detail/Rokit6G3
http://www.sweetwater.com/store/detail/Rokit8G3
Otherwise, just do a search on "active PA speakers" and choose one that fits you needs. The links I gave are just from one vendor and small sampling of what is out there. Bose! Pah! Buy Other Sound Equipment. You want to look like a professional, right? You need professional equipment.