If I put a straight edge e.g. ruler across my Technics SLD150, then I see that the mat gradually thins out going towards the middle. So when mounted the LP creates a hollow area underneath. Why did they design it this way?
If I set azimuth at vertical then I am happy. If I then put a clamp or weight on the centre I am playing the majority of the record with azimuth out.
No mention in any Technics manual about this hollow, surely this is is detrimental to the sound? Maybe not?
Any thoughts on this mat design? Do after market mats resolve this?
Steve