A $300-$400 turntable tweak

Halcro, thanks for starting this thread. Very ear-opening. It never occurred to me to try my VPI HRX without the periphery clamp as it came with the turntable. Based on one weekend of listening the table seems to sound better without it -- slightly bigger sound stage, more open and lively. This was with the Airtight PC-1 cart and 2 drops of damping fluid in the JMW 21.7 arm Tnx again!

P.S. - When comparing having the ring on or off I found it required a 0.04 Hz frequency change on the SDS to get speed to match. YMMV.

Perhaps some of the difference we hear with rim weights is due to whether we use a mat on the platter. On my Transrotor Fat Bob, there is no mat, just a vinyl layer which mates with the record. It is hard and has no give so the rim weight just makes sure the record is perfectly flat at is in contact with the platter at all points.
If a rim weight was used with a soft mat, I can see where it might press the record into the mat, causing a different resonant experience than just laying on the mat. I havent tried a soft mat on my Transrotor, and the only one I have is the Oracle mat which is quite soft and squishy.
for the record, I like the sound with the rim weight and center clamp.

As Manitunc and others here have suggested.........I believe that it may be the mat in combination with the rim weight which is the culprit here?
I removed the Millenium mat from my Raven AC-3 and placed the record directly on the copper top platter together with a centre weight and the rim weight.
All the life and magic, which had previously been sucked from the presentation with the mat in place, suddenly returned.
I am unable to repeat this experiment with the Victor TT-81 DD table as the aluminium platter has a raised outer rim to contain the thick rubber mat, and without it, the record's outer edge sits upon this rim and thus does not make contact with the platter itself.

Is the sound quality without the Millenium mat on the Raven but with the outer rim weight, better than a record without the rim weight but WITH the Millenium mat?
Not really.
So unless I'm playing a seriously warped record (and I only have a few which cause problems), why would I bother with the fuss and ceremony involved in the placing and removal of the outer rim?