The phrase "quality sound" refers to sound that is clear, crisp, and pleasing to listen to. It means that the sound is of high standard and has good audio characteristics. Full definition
If you like to listen to music, look at a higher quality sound system. (educationworld.com)
The room is equipped with a TV and DVD / CD player and the high quality sound system is linked via a portable iPod docking station to speakers throughout the villa. (villamako.com)
Of course a single bottom - firing speaker isn't the best configuration, but it does well enough to provide basic quality sound with good volume. (androidheadlines.com)