To add a layer to that, maybe run the 10 trial 3 times in a row with some time between them. That gives 3 seperate trials but without obvious excuses of listening fatigue. Without the ABX box coin flip may have to do, but time between cables would be an issue there.\n\nAnother consideration to your trek into all this are these two documents:\n"High-Resolution Subjective Testing Using a Double-Blind Comparator", Clark, David, Journal of the Audio Engineering Society, Vol30, no 5, May82, pg 330-338. \nFig 2 is telling about level differences for detection over bandwidths.\n\n"Level discrimination as a function of level for tones from .25 to 16 kHz" Mary Florentine et al; Journal of Acoustic Society of America, no 81, (5), May 1987, pg 1528-1541.\nJND (just noticeable difference) with test tones, headphones, very sensitive, more so than what we listen to. At 10kHz, it is at 1dB, 16 kHz is 3 dB if you can hear 16 kHz. ;) \nUnfortunately it didn't go down to the low bands but that 1st paper, fig 2 is of interest.