The short answer is "no." Most people use normal bookshelf or satellite speakers as their surrounds, and they do a fine job. But if you really want the best home theater sound, then there are speakers designed specifically for surround sound known as dipole/bipole or solid/diffuse. Each of these speakers has two sets of drivers, with a switch that lets you select dipole mode (out of phase) or bipole mode (in phase). If you're mounting the speakers on the side walls in line with your listening position, the dipole mode will create a diffuse, ambient soundfield. If you're placing them behind your position, the bipole mode fires the drivers in phase to flood your room with surround sound.
