Screw-down reflex clamps vs. record weights

Peterayer - interesting hypothesis of yours that when people report an improvement on changing from a screw-down clamp to a record weight (of the type we are discussing) this may actually be due to some sort of 'decoupling effect', i.e. the record weight, precisely because it does not optimise transmission of resonances through the spindle/main bearing channel, may in fact help to stop bearing noise being transmitted upwards through the splindle into the disc.
You conjecture that, the noisier the main bearing, the more likely it is that a record weight (as opposed to a clamp) will have a beneficial effect.
Of course, it is true that some turntables have noisier main bearings than others, but surely practically all main bearings produce some degree of resonance or vibration. So even our SME turntables (mine a Model 30/2) - with their fantastic main bearings - are still producing some noise, albeit to a degree that we would normally consider negligible.
So I wanted to ask: as a long-term SME user, have you ever tried a record weight as an alternative to the SME reflex clamp on either of your SME tables? Have you ever tried either of your turntables with no clamp at all (i.e. leaving the SME clamp off)?

Hello Pgtaylor, I have not tried any alternative clamping/weight systems to what is supplied with my SME tables. I did try listening to my SME Model 10 without the clamp and spindle washer. I thought the sound became a bit less clear and dull, but that was a long time ago and I can not recall the specifics.

Prompted by this thread, I did some more extensive listening on my SME 30/12 with and without the SME clamp and washer system. The results in general seem to be about the same as with my Model 10 but as this system is more resolving, the difference seems more pronounced.

I listened to selected tracks on three LPs in A-B-A or B-A-B order:
1. Vivaldi, Les Concertos Pour Mandolines
2. Ellington/Brown, This Ones for Blanton
3. Johnny Harman, Once in Every Life

The Vivaldi is very difficult to reproduce well because of the complex harmonics of the mandolines and harpsichord. Sure enough, without the washer and clamping system, dynamics were dulled, leading edges were not as crisp and harmonics were rolled off and blurred. On the Blandon and Harman, bass, piano and voice had less weight. Overall tonal density was diminished slightly. I'd say the sound was less vivid.

The differences were not huge, but I was very pleased to get the old sound back with the washer and clamp. Interestingly, I also tried one cut with the washer and no clamp. This raised the LP off the platter surface and the result was terrible. The LP slowed down so much with stylus drag, that is sounded almost like a 45 played at 33 and speed shifted with more or less stylus friction. It makes me wonder about playing an LP on a hard platter surface like brass or copper with no clamp, but many people do this with reportedly good results and hear more "air".

So, at least with my SME tables, the washer/clamp system seems to flatten the LP against the platter and improve the LP/platter interface for improved sonics. Whether this helps to drain energy from the cartridge away from the LP into the damped platter or isolate the LP from bearing noise, I don't know, but I much prefer listening as recommended by SME.

Many thanks, Peterayer, for your interesting post.
It does not surprise me that playing records on the SME without some form of clamping gave a less satisfactory result than using the standard reflex clamp. This is also my finding. And of course if you leave the washer in place when not using the clamp, the results will be dire! In that case the disc is simply not stabilised and will in all probability wobble (this would be the same on any turntable). You will also have changed VTA.
Personally I had always used the SME clamping system on my Model 30 (it was no stranger to me since I had previously used the Sota Reflex Clamp on a Goldmund Studio). About a year ago I happened to use a record weight (the Sutherland Timeline, which has a thick delrin base so that it can be used for disc-damping purposes) and found that this also worked quite well. The result was different from that obtained with the SME clamp: more laid-back, maybe in the end not quite as clear. I continue to prefer the SME clamp on most records, but I have begun to think that a record weight could also do a very good job on the SME.
Since the Timeline's disc-damping function is more or less an afterthought, I suppose that one can do better (read: Kuzma Ebony, Hauer-Analog Bubinga or HiFi Tuning VRO).
So the question is whether one of these (supposedly) optimised record weights would do a better job than the SME clamp. My money is on the HiFi Tuning VRO, which appears to be a carefully thought-out device.
Regards,

Peterayer - my Final Audio has a 4.8kg copper mat with an indent for the record label. With the VDS-17 1.8kg gunmetal weight and washer, it is crisp, articulate and very detailed. I tried a 300/400gm weight instead ( with the washer ) and the sound lost articulation and detail - the top end sounded rolled off, lacking extension and detail. We are talking $2000 cartridge versus $10 old Grado kind of difference here, not minor.
I strongly suspect that 300-400gm is insufficient for coupling with a washer type system. It may be insufficient to do much on a concave platter in terms of effective coupling. It may dampen resonances but I would seriously question whether the difference is large in that application.