I've had some correspondence with Larry, the seller of the rings in the link I posted originally. He does address the possibility of the ring being non-concentric as follows (I hope he doesn't mind my posting this information, but it does help explain how to best use this ring and remove buyer concverns, and as such I would think it is helpful to him and his sales effort):
(begin quote) "Big issue records vary in size .100 so lots fit without setting but the exceptions must be considered, lots of tweaking now, we actually made 14 different shapes and sizes for testing.
1 - If the ring runs out less than .015 no issue with speed etc. No affect
2 - If the record is a small old A&M pressing the outer ring setting disk tool must be used that set the disk with .005 concentricity
3 - If the Record is on top limit on diameter we have enough room to make the ring concentric with the disk
4 - some albums are not concentric and I use them successfully because they are out no more than .015 and that really does not affect playback
The Disk is simple it is a recessed (counter bored disk, same diameter as the ring, with a spindle hole bored in it). Place the record in the disk and put it on the TT and remove. It also stores the outer ring nicely, it is machined with ) run out form the diameter to the spindle hole and you can get the album concentric with a few
thousands if you are careful. I have tested every LP size/manufacturer and condition and thus far it is flawless." (end of quote)
I guess time will tell. I would be anxious to hear impressions from anyone who purchases one of these new rings and their listening and usage impressions.
Bob
(begin quote) "Big issue records vary in size .100 so lots fit without setting but the exceptions must be considered, lots of tweaking now, we actually made 14 different shapes and sizes for testing.
1 - If the ring runs out less than .015 no issue with speed etc. No affect
2 - If the record is a small old A&M pressing the outer ring setting disk tool must be used that set the disk with .005 concentricity
3 - If the Record is on top limit on diameter we have enough room to make the ring concentric with the disk
4 - some albums are not concentric and I use them successfully because they are out no more than .015 and that really does not affect playback
The Disk is simple it is a recessed (counter bored disk, same diameter as the ring, with a spindle hole bored in it). Place the record in the disk and put it on the TT and remove. It also stores the outer ring nicely, it is machined with ) run out form the diameter to the spindle hole and you can get the album concentric with a few
thousands if you are careful. I have tested every LP size/manufacturer and condition and thus far it is flawless." (end of quote)
I guess time will tell. I would be anxious to hear impressions from anyone who purchases one of these new rings and their listening and usage impressions.
Bob