Loudspeakers will sound differently depending on the environment in which they are set up. Therefore, it is not surprising that if you have listened to the speakers in the dealer showroom that the sound at home is quite different. I will give you some pointers for improving the sound quality of your loudspeakers.
First of all, the location of the speakers is crucial. You never want to set up a speaker close to a reflecting wall so that the sound bounces off the wall. Generally, the speakers should be rotated such that the front is facing towards the middle of the room. If you have to speakers then you might want to position each speaker in one corner of your room. The front of each speaker should be facing towards the middle of the room. Make sure that neither speaker is closer than 3 feet to the wall. If the speakers are any closer, chances are the wall itself will affect the sound quality. The more reflected sound components exist, the more the sound will be affected by obstacles and walls.
Further, make sure the speakers are positioned on soft pads such that no vibration will be transferred between the speakers and your stand or floor. You might want to consider purchasing some speaker spikes which mount at the bottom of the speaker enclosure. The spikes will keep the speakers locked into place and also minimize the transfer of vibrations.
Next, make sure that the power amplifier is able to drive the speakers properly. Check with the manufacturer of your amplifier that the speakers are supported by the amplifier. One indication is the speaker impedance. Also, check the speaker wattage. You never want to overdrive speakers. Over driving the speakers can damage to speaker diaphragm and thus cause distortion down the road. Also, the speakers should not be driven to the maximum rate wattage. The higher the speaker diaphragm is excited, the higher the amount of distortion of the speaker will be.
Also, in order to achieve proper stereo separation, you should separate the two speakers at least 5 feet from one another. If you locate each speaker in one corner of your room then you should have plenty of stereo separation. Another alternative arrangement is to locate the speakers close to one another and rotate them such that the sound of each speaker is radiated an angle of 45°. The sound should be radiated towards the walls such that after the sound components are reflected, you will experience the same effect as if the speakers were actually separated quite a distance.