Speaking of DBT's, there were some published in these:
Masters, Ian G 'Do All CD Players Sound the Same?' Stereo review, Jan 1986, pg 50-57.
Pohlmann, Ken C. '6 Top CD Players: Can You Hear the Difference?' Stereo Review, Dec 1988, pg 76-84.
Pohlmann, Ken C. 'The New CD Players: Can You Hear the Difference?' Stereo Review, Oct 1990, pg 60-67.
Some of these players are OLD, but according to the DBT results the differences were audible to a statistically significant degree. And one test not published in a magazine but in a club newsletter discovered a broken digit in a 14 bit player. Today's players are much more difficult to differentiate if not impossible.