Everything else was the same...I heard no discernible difference whatsoever. Now, I'm not saying S/PDIF or USB cable isn't going to make a difference - for they may. But, after spending 3500 for the DAC and another 500-1000 for the cable...you'll have to be the judge as to whether your hard working dollars is worth the expense in the degree of difference you may (or may not) hear.
Also, I think how you're listening to the music matters too. If you're critically listening to the music (studying the shyt out of it and not enjoying it but trying to hear the micro nuances) - or - merely relaxing with a glass of wine or favorite micro brew then (perhaps) those micro nuance changes will go completely unnoticed.
One last thought...any cable can start to sound good - after you've had it plugged in for countless hours (and happen to know the commercial drive behind the name) and price tag (IMHBAO)
Good luck.