As a middle-aged rock fan, I have a problem many of my peers would relate to: Every year, more of my favorite musicians die, and every year, the list seems to get longer. If you've been listening to them for decades, every death is a painful blow. It took me a few days to get over the recent loss of the Fall's Mark E. Smith; my wife was stricken when the Cranberries' Dolores O'Riordan — who was my age — suddenly died last month.

I'm not sure, though, that I'm down with the way some innovative companies are trying to fill the void.

I understand the economics behind last year's European tour by the hologram of onetime Black Sabbath singer Ronnie James Dio and the recently announced holographic resurrection of Roy Orbison. But I wish both tech entrepreneurs and the musicians' estates allowed stars to rest in peace.