Hi, if by "transparency" you mean each instruments fundamental tone and its harmonics are reasonably full; inner detail is available; and transients are reasonably fast, then I would take a look at: sonus faber, living voice, magnepan, legend von gaylord, audio kinesis, fal, kharma and verity. I'm sure there are others, but thats my short list. In other words, instruments do not sound "rolled off", even though their central tone may be beautifully reproduced. And the 3d image of various instruments can co-exist without cancelling out one another.
It seems that SET is often referred to as transparent, and often it is transparent. However, just as an example, there are many SET setups that choose to emphasize the central tone or timber of an instrument, especially a female voice, rather than choose to emphasize the whole range of an instrument. Sometimes this takes the shape of sounding rolled off and sometimes it does not sound rolled off, but one portion (low, middle, high) is emphasized over others. I'm not saying one is better than another (vanilla versus chocolate debate), just that to me, transparent means conveying as much of the whole range of each instrument. Further, some setups (SET or otherwise) will convey the whole range of the foremost instrument in the recording and will push the supporting instruments into the background. To me, this is not transparent.
Lastly, it seems there is a fine balance between transparent and an overly aggressive top end. IMHO it is difficult to find speakers that are both transparent and don't rough up the ears in the high end. Anyway, I've heard all of the foregoing convey transparency as I've loosely tried to define it.
IMHO/YMMV/ETC. Jeff
