For clarification, I want to point out that the washer used with the Sota Reflex Clamp is made of felt. When I bought my Sota tt and clamp many years ago, it came with two or three of these felt washers. As mentioned, the washer makes a big difference in coupling the record to the platter with the reflex clamp. As far as I can tell my platter is flat, except for the slight relief near the spindle that is about the same diameter as the record label. The Sota reflex clamp flattens the record out to the outer edge with the felt washer under the record. Without the felt washer, I think the record would dish when applying the reflex clamp.
I have a couple of records with funny warps that make the outer edge roll up on one side when I clamp them down, but they are coupled to the platter the rest of the way in. I experimented years ago with and without the clamp. I don't remember hearing a big difference, but I use it everytime because many records will not lay perfectly flat on the platter without it.
I have a couple of records with funny warps that make the outer edge roll up on one side when I clamp them down, but they are coupled to the platter the rest of the way in. I experimented years ago with and without the clamp. I don't remember hearing a big difference, but I use it everytime because many records will not lay perfectly flat on the platter without it.