... Massed violins in their upper registers (1500-3500 Hz) OFTEN [emphasis added] jump out from the mix and sound a bit harsh, unlike what one hears live.As I read it the information provided does not exclude the possibility that it may be a recording issue, as Rok2id suggested.
Have you found this to occur with orchestral recordings that you know to have been recorded with "purist" microphone techniques (e.g., 2 or 3 well placed mics), and that you can say with confidence have been well engineered in other respects? Or have all of the recordings on which you have perceived this problem been heavily multi-mic'd, with the forest of microphones that are typically used for orchestral recordings released by many of the major labels?
Regards,
-- Al