[header] How to determine the quality of a stereo [title] Look for stereos with full-dynamic range. [step] " range " essentially refers to how many types of sounds a stereo receiver can produce. Systems with a " full " range (between 20-20 , 000 hz) will sound much more crisp and detailed than those with restricted ranges. 
This is one of the most important factors in determining overall quality. [substeps] You can usually find a stereo's audio specifications on the packaging, or somewhere on the unit itself.