from
http://www.unconservatory.org/articles/goodmusic.html
1. It the piece technically well executed? Regardless of the style, the performance - whether improvised, derived from notation, or electroacoustically produced - should be free of extraneous notes, sounds, effects, nuances of any kind that do not contribute to communication of the musical ideas.
2. Does it exploit a variety of elements of music, i.e. rhythm, harmony, melody, texture/timbre? Although a quality piece of music need not have all elements equally represented (in fact, many if not most fine works do not), a piece that relies solely on any one element is likely to be less than fulfilling.
3. Are the elements of the work highly integrated so that each supports the other’s function? Melody, for example, cannot exist without at least some degree of rhythm; rhythm, however, can exist without melody, as can harmony without either rhythm or melody. But it seems that most truly satisfying music exploits the elements in ways that cause the product of them to be greater that the sum of the elements, disparately.
4. Does the piece appeal on a variety of levels – intellectual, emotional, spiritual? A piece can be strong enough in any one of these areas to justify being called good, but the best music somehow seems to appeal on many levels.
5. After having been listened to many times, does the piece still have appeal, appeal that is based on some new revelations rather than solely on comfortable familiarity? Complexity in and of itself is not especially valuable, but exceptional music seems to have many facets, and holds up well and continues to interest even after many listenings.
6. Is there a good balance between familiarity and variety, appropriate for the length of the piece? Clearly, very extended pieces will need to introduce more variety than very short ones; likewise the task of maintaining coherence within greater diversity is more difficult and expected in longer pieces.
