Ok, it's not fair to say I can' hear them. The difference between the 'Original CD' track and the others is huge. But the very subtle changes I made along the way I find quite difficult to detect.
For example, the difference between two of the tracks is primarily the clicking of the 'bass' button on the concrete limiter and then adjusting the levels again and getting the track average loudness to fall around the same spot.
So, this amounts to clicking a button that makes it louder then pulling the fader to make it softer again. the net change in volume of the bass is difficult to detect. The only way to hear it is to detect the difference in limiting which I find quite hard to hear when I'm jumping from one to the other.
In theory, I should be able to just listen, eyes closed, and be able to say which bounce I'm listening to. I don't do a great job at that. Some differences are more detectable, but a number of the bounces are quite close to each other.
Thanks for listening and giving your feedback by the way.
I created a survey monkey survey...
https://www.surveymonkey.com/s/JDRYHMN