Believe me I am not one to believe all the BS that many audio manufactures push on people. I would agree that most cables don't do much. But certain cable manufacturers cables can make a significant difference in my opinion (MIT cables for one. And yes they are grossly over priced). Could I pick them out in a DBT. Probably not. But I doubt I could reliably pick out amps and preamps in a DBT either. In fact if speakers were matched for decibels and both had a similar bass output, it would probably be hard to pick out speakers in a DBT as well. So does that mean there are no differences? Maybe or maybe not.