Aren't the two tables best optimized with different tonearm, and cartridge plus also set up and calibrated differently? Any combo of these could account for a difference. Not to mention dirt accumulated on the stylus, etc.
It's not as though we weren't aware of any of those variables. Everything was checked and rechecked with the same result. What I am describing was a the result of the platter being unable to maintain angular velocity which would have been well known to a turntable designer or other expert but not to us at the time. Live and learn.
II have a training that permit to know in " hours " what you could take " many months ". I already explained this to you in other thread even you " live " how fast I can detect " errors " or virtues due to that specific training.
Well, if I had only known this beforehand. I am now bowing from the knees.
John