Moby Dick wrote:
You literally pointed to results that say "Trained listeners can hear the difference between CD quality and MP3 compressions." AND "Trained listeners can not discriminate between CD quality and Mp3 compression (320kps) while expert listeners CAN."
EXACTLY. I am an expert listener. I have a high quality set up that includes preamps, amps, and HIGH end speakers and headphones. Audio quality is distinguishable easily on my setup, including to my wife who hasn't a clue.
You actually have it backwards. When comparing the very low end, speakers matter more than the audio quality.
ANY listener can tell the difference between $20 buds, $75 over-ear, and $200 beats, even with 128kps quality off an iphone. Your analogy of racing tires making a Honda faster is not quite accurate. $20 buds are like a square wheel, you'll notice the difference on anything.