[Wayner]

Wayner, why do you think a screw down clamp makes more sense?

Well, there is less weight, which is a concern for posters (me, too), and you can vary the pressure exerted by how much you screw down on the clamp.

There are at least 2 camps here. Clamps vs weights. Weights are easy, because most simply slip on over the spindle (as does the one I made), clamps either are threaded onto an existing threaded spindle (in the case of VPI, others) and some other clamps have built in mechanisms of one type or another to grab a plain spindle.

If we go with the VPI type screw down clamp, that has a rubber washer underneath the record. My question then is, are we not then turning the record shape into a cone? And if that is so, then the cartridge azimuth now been compromised.......

Wayner

[tomytoons]

It is always try and listen. Platter material, thickness, mat, Screw down collet system, table suspension, all change the sound.

I have had more than a few nice clamps and weights here.
Currently on my P5 I use Herbie's Super Sonic Stabilizer. I also purchased a used Basis Super Clamp. I wouldn't pay new ($350+) for this but it has to be the nicest piece of engineering of all the collet mechanism type clamps it has a rubber O ring around the base perimeter, and better than Turntable Weights. Extremely easy to use with a 1/4 tun on and 1/4 turn spring snap off. Beautiful, just had to have another like I had on my 1400. I don't use it all the time because it still might suck some life out of my P5 Delrin platter combination.

I would say yes to the washer changing the cartridge arm set up a bit, but can you hear it? Probably not.

[Letitroll98]

If we go with the VPI type screw down clamp, that has a rubber washer underneath the record. My question then is, are we not then turning the record shape into a cone? And if that is so, then the cartridge azimuth now been compromised.......

Wayner

Not really.  The washer is fairly thin and goes on the spindle in the very center of the record.  The clamp is hollow at the center, clamping in a ring around the where the center is raised.  This has the action of flattening the portion of the vinyl that has recorded grooves.  While I'm sure not perfectly flat, it's much flatter than records placed on the platter without a clamp.  Vinyl's plasticity has a role here as well, it doesn't cone up like if you where doing this with a 12" metal circle.  That being said, the VPI Ring Clamp in the final piece for a full solution.

[Douger]

I sometimes use a Keith Monks weight with my TTWeights Stabilizer Ring to defeat warps  - it does darken the sound a little sometimes, but beats warped sound. IIRC, it weighs 17 oz.
I have also made a lighter weight out of a coffee  jar top and lead shot just in case.
Finally I have an old Radio Shack clamp, very lightweight. That is the item I miss most from them.
All that said, I usually do not  use one at all

[J-Pak]

I sometimes use one made out of a solid piece of ebony, it's not that heavy. Sometimes I can't tell any difference with it on, and on some records it helps solidify the image.

[jimdgoulding]

I use an Orsonic heavy clamp.  My recordings sound richer and more liquid with it in place.  I use it on both my belt tables.  No expense to anything good that I can tell.

[simoon]

I've always been a fan of clamps or weights.

Clamps on suspended tables, weights on non-suspended.

I hear improvements with them. Especially with purely acoustic music, like chamber music.

 

[pumpkinman]

I just ordered this one from ebay

[simoon]

I just ordered this one from ebay

I have one of those protractors. It's pretty good.

[Lifer]

I have two different ones that I choose between depending on the lp.  For heavier lp's (150 or better I would guess) I use a brass weight/clamp (has a plain-spindle grabber) that weighs 12 oz.  For light lp's like recent Deutsche Gramophone's or most 1980's rock the brass is too heavy and causes the edge of the record to lift - a concave disc due to the label depression in the mat, so I then go to a Mitchell clamp (with the center washer,although I made my own from silicon rubber) which locks the lp to the mat. 

I also use the Mitchell for warped lp's.  I understand the concern with making the lp into a convex disc (a cone) but the center lift is about 1mm so the convexity is tiny and far less disturbing to azimuth than even a slight warp would be.

Always the idea is to maximize contact with the mat to absorb vibration and to stop the lp from slipping: both of these due to needle friction.

[bogiedr]

I use the plastic clamp provided with my Clearaudio Emotion table. I will say I have tried this clamp with my Luxman PX 100 and Technics SL 1500 ... not sure why I use the clamp! I have tried the Clearaudio without the clamp and can't tell a difference!! 

[doug s.]

my oracle, which i have used for >10 years, comes with a screw-down clamp.  this, combined w/its platter that is ever-so-slightly concave, means it is wery effective in coupling the record to the platter.  it works great, and allows the wery few otherwise unplayable warped records i own to play yust fine.  prior to the oracle, i used an audioquest clamp on my c&j walker turntable, and that, combined w/a record mat and a small bead of window insulation at the platter's perimeter, mimic'd the oracle's platter/clamp system, but it did not work as well - there was one single record i could still not play on the c&j walker...

doug s.