My answer...
I grappled with this exact question when creating the Enchiridion of Mystic Music. Free of Charge, here is the answer I came up with (note that it makes Bardic Music - "mystic music" below - about equal to low-level magic with a range of Medium). Hope it helps someone... and *shameless plug* if you like it, go buy the book from RPGNow.com!
--The Sigil
Range
Most mystic abilities can be used to affect anyone who can hear the user. Some, however, require close proximity in order for the effect to work and others require that targets be able to both see and hear the musician. Common ranges are detailed below.
·Hearing: Under normal conditions, hearing range is a 120 foot spread (i.e., it can turn corners and so forth). The spread can make its way through solid items (such as doors and walls) at a cost of 10 "feet" per point of Hardness possessed by the item. Treat areas of silence as though they were impenetrable walls of force for determining the reach of the spread. This is the range at which a single musician can be heard sufficiently well to affect a target with a mystic music ability. Each additional musician beyond the first increases the range of the spread by 40 feet (while not strictly correct physically, it is the "closest fit" for groups of fewer than 8 musicians). If the musician is playing in conditions that would hinder Listen checks, this range is adjusted by –10 feet for each –1 penalty to a Listen check. This means that a musician playing in high winds, for example, where a –4 penalty applies to Listen checks, would have hearing range reduced by 40 feet to a total of 80 feet. A musician may always choose to play more softly and decrease the hearing range.
Note that it is possible to hear the music that a musician is playing outside of this range; it is simply too indistinct to allow the effects of the mystic music to be effective. Anyone attempting to perceive that the musician is playing who is outside of the "hearing range" must succeed at a Listen check (DC 15 + 1 for every 10 feet between the subject and the hearing range). For example, in normal conditions, a character 200 feet away from a musician who attempts to Listen to see if the musician is playing must succeed at a Listen check against DC 23 (he is 80 feet outside of the hearing range of 120 feet, so the DC is 15+8).
·Sight: The musician must have a line-of-sight to the target in order to affect the target. Sometimes the target must also have a line-of-sight to the musician. The rules for determining line of sight should be used as normal to determine whether or not this condition has been met.
(EDIT: EXAMPLE IS FASCINATE)
·<x> feet: Some effects are only effective within a certain range (usually this range is shorter than hearing range). If conditions would reduce hearing range to less than the designated range, use the hearing range value instead. This gives the range at which the effect can work and is not adjusted for conditions except as already noted (i.e., when hearing range is so drastically reduced by conditions that it is shorter than the listed value).
