A fundamental property of human perception is that it is variable. The same person experiencing the same thing on different occasions will have a slightly different experience of that thing. Different people experiencing the same thing at the same time will also have slightly different experiences of that thing. That is why measurement of psychological phenomena typically makes use of samples of data. If each person's experience is measured using a psychologically valid scale you will get a distribution of measurements with an average value and a degree of variability (e.g., standard deviation or statistical error). This enables you to say whether two distributions of data are different from one another (or not).
So, invite a dozen buddies over to listen to each cable (not telling them which is which) and have each of them rate each cable using a psychologically valid metric (a 7-point scale anchored with the labels Like Extremely, Like Somewhat, Like Slightly, No Opinion, Dislike Slightly, Dislike Somewhat, Dislike Extremely would suffice) and you will get an average and a standard deviation for each cable. Calculate the Mean and 95% Confidence Interval for each distribution and if the two don't overlap, well, then, pick the cable with the highest mean Liking.
You can see that this takes a bit of work, but that is what is required for a psychologically valid answer. I have actually done such research for several corporations at which I have worked. Same thing applies for visual and tactile experiences.