It depends on the software you are using. Hence why you are getting poor answers. Different software uses different formats. Give out this information and I'm sure you'll get a better response.
Most module tracker programs will load any >>uncompressed<< format but you might need to chop the front(data) part off. If you get a screech then you are using the wrong type (signed vs unsigned).
Clarity is measured in two ways.
How many bits normally 8 or 16 bit
and the speed of playback in Hz. 25..50hz should be ideal for the Atari.
I'm no music expert so this information is an indication and I might be wrong but this should hopefully get you started.
The problem with quality is disk space. So experiment, it's the best way to learn.
