Bard Instrument Confusion (xxxx Instruments: ##)

[myxomatosii]

Simple question, why don't all bard instruments have a rating like some of them do. For example this similar wind instrument that I would've thought nothing of (it has no rating!) until I noticed it drops from a God and has a high cost. There must be some way to classify all of these different instruments with no stats in some quantifiable manner...

Sorry if this is a dumb question, I didn't get many results back from search as I'm new to bard and wasn't sure what I was looking for.

Edit: Link to every weapon I found that has what I'm talking about below.

http://wiki.project1999.org/index.ph...lute_of_Flight

http://wiki.project1999.org/index.ph...Gypsy_Princess

http://wiki.project1999.org/index.ph...e_Battle_Drums

http://wiki.project1999.org/index.php/Sharkskin_Drum