A good system in a bad acoustic room will sounds just as bad. That is why room acoustics is very important and should be dealt with in order to truly enjoy your HT or hi-fi system.
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Home Theater Acoustics
One of the first things the novice acoustician does upon entering a room is to deliver a sharp clap of the hands. This is followed by a grave shake of the head and comments about how bad the room sounds. Next comes a proposition to fix the room and the fee. The unsuspecting client then administers a sharp hand clap, nods the head in agreement, and gives the guru a retainer. The only problem here is that these people are busy buying and selling modifications to the sound of their own hand clap. We don't listen to a speaker while holding it in our hands, yet we can be tempted to consider acoustics based on the sound of our own hand clap. THE ACOUSTIC CLAP TEST
A hand clap contains only high frequencies. For a loudspeaker, the high frequencies are directional, forward of the speaker box. To properly administer a hand clap that mimics the high-frequency beaming pattern of a loudspeaker, the hands must meet at waist height while the clapper is facing the same direction that the speaker does. The body of the clapper blocks the expansion of the clap sound backwards. The listener is no longer in the clapper position, the listener is now seated in the listening position. This time, the hand clap is cast forward from the speaker position and is heard by the real listener. It is how the listener hears the speaker that counts and not so much how the speaker sounds to itself, at least in hi-fi playback settings. 
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