Assuming he is interested at all, your test should strive to prove to him that you can tell a difference rather than to prove to him that he can tell a difference.
I would be much more interested in such a test if I were him. I know I am much more interested in finding out if you can tell a difference than if he can because you have said you can and you listen to music and he may not really be into music.
I have participated in this kind of thing several times with widely scattered results.
The easiest was with the diamond I bought my wife when we were engaged. I had looked through the diamonds and picked out two that were of good quality, cut and color. One was a little larger by carat size and had a bigger face. The other was slightly smaller and had a smaller face which was mostly smaller due to the better shape of the cut it had rather than the carat size. Both diamonds were good, but the smaller one out sparkled and out shown the larger one due to its far better shape. (The proper shape of the smaller one put more diamond below the face and caught and reflected light better than most diamonds which are improperly cut to have a large face to fool people into thinking they are getting their moneys worth.) The diamonds were attached to little cards with the identifying information listed on the back. I told her I knew which one I liked but that she should pick from the two. She picked the smaller one with the bigger sparkle. I was happy with this and the salesman was very intrigued at how this was proceeding. We were both thinking the same thing when he asked if we would like to see if she could pick the diamond out after swapping them around. I said yes and that I was certain she would be able to do so. We swapped the diamonds around while she looked the other way and she picked it 3 out of 3 times. We had the right one. Although it is not particularly big, (it's less than a carat), it shines particularly bright and people have noticed it and commented on its brilliance. I don't wear my jewelry myself and am not particularly interested in it, but that diamond is brilliant.
In college, we were talking beer preferences when I stated the heresy that there wasn't much difference between the mass produced American rice water beers they claimed were so different from one another. I mean there just isn't much taste to be had in Busch beer or Milwaukee's Best. (We called it the Beast, it was cheap and available.) We poured the beer in two glasses and noted which was which. Most couldn't identify the beers correctly 2 out 3 times. They were somewhat disappointed. I then told them that I believed I could tell the difference and this got the whole thing going again. I was able to identify the Beast at least 2 out of 3. I told them that I was only able to do it not by flavor differences but because the Beast had more of a watery consistency and the carbonation was different. I can't recall if it was flatter or had bigger bubbles but it stood out. I went back to drinking Olde Heurich.
