To Clamp or not to Clamp, THAT is the question!

I've read both pros and cons during a search here about using a record clamp, so I throw it out to y'all for suggestions.


I have the following rig:

Denon DP-62L Direct Drive Turntable
Shure V15, Type IV MR Cartridge


Given that some folks here think there could be detrimental effects to the TT of an incorrect match between platter / drive and a clamp, I'm thinking of getting something pretty lightweight, and only using it on vinyl that is fairly warped.

In one thread a poster (who doesn't list his equipment) said:

"I use a 1 inch long piece of 1/4" rubber gas line. Makes a great, inexpensive clamp."


The price is certainly right -- does that seem like a good option?

In any case, I'm open to any and all advice either way (i.e. brands, models, etc. if you recommend I get one).

Thanks much

.

 

Call me cheap, but I bought a hockey puck for $3 and drilled a 15/64" hole in the center without actually drilling all the way through. This now acts as a great clamp, because the hole is small enough that it tightly grasps the spindle. I need to screw it down onto the record. It doesn't damage the labels at all, and I have noticed improved sound stage and detail while using it. It does also help with some warps, not all though. I highly recommend giving this very cheap alternative a try. The puck is also light weight, so it doesn't stress the motor like some other industrial weights would.

 

I use a clamp with my Sota. To my thinking, it works pretty well, but might not work so well if the table was less quiet in general, as you are most likely creating a stronger bond not only between the platter and the record, but the spindle as well, which is rotating on a bearing.

 

Clear Audio twist clamp - always.

Cuz I like routine and hate change.

 

I use J A Michell clamp which I like because the record is decoupled from the platter by a felt washer and secured by the clamp. Takes care of all your rumble concerns.
http://www.ebay.com/itm/J-A-MICHELL...896?pt=LH_DefaultDomain_0&hash=item5673aa1950

 

How is the record decoupled from the platter?

 

I use the screw-on record clamp provided with my Oracle Paris MkV. I really like it as I can apply as much or as little torgue as needed.

 

Jupiterboy,The record is decoupled from the platter by a felt washer which is placed around the spindle so the record is suspended off the platter and kept that way by the clamp... simple and effective.

 

My Avid table is designed to be used with a clamp.

 

The weight, type of clamping system, and material used will all have an effect on the sound. Some tables sound best with no clamp at all. Sometimes a lighter clamp such as the thin plastic Clever Clamp is the best and sometimes a very high mass clamp will sound better. DIY clamps are great. I've tried clamps that have, one way or another, killed the sound. Another situation that you must watch out for is that many mats have a deep label depression, meaning that when you place a heavy clamp on the vinyl, you will press down on the record causing the play surface to lean inward toward the spindle and become non-level. So the only way to answer the question is to experiment with different clamps until you find something that you like. Also, for suspended table users, make sure you adjust the suspension to accommodate for the extra weight of whichever device you decide to use.

 

I don't believe that's the way the Michell clamp is intended to be used. It's operation is similar to the VPI clamp, where the washer raises the center of the LP slightly so that the clamp can force the rim of the LP down on the edge of the plater, both flattening the LP and improving damping. If the LP is not touching the platter the clamp is not being used correctly.

http://forums.stevehoffman.tv/threads/question-about-michell-record-clamp.279155/

John K.

 

No clamp. I like as few steps as possible between me and my music.

 

The Avid system works pretty nice. The brass top of the bearing/spindle is raised a tiny bit from the platter, and the clamp has a ridge around the outside on the bottom.

When clamped the vinyl is coupled nicely with the platter.

 

I use a weight. Works fine.

 

A clamp won't help a warped record very much, because warps are out around the edge, and the clamp is in the middle. And the whole point of a clamp is to make a tight connection between the record and the mat. And the reason we want to do that is so that the turntable will absorb the tiny sounds created by the vibrating stylus (a record is actually a mechanical loudspeaker in that regard). I use a Michell myself. It's not a night-and-day difference, but I did notice the bass became more taut with the clamp. Clamps are better than weights because weights put extra load on the turntable bearing.

 

I have never used a clamp on any of my turntables as I could never see the benefits. It would increase the rotational mass but wouldn't have much effect on warps because the warps are usually at the edge.
As far as making a record sound better, the only way I could see this happening would be if the clamp were made out of vibration absorbing material.
Being a jukebox guy, Seeburg clamped their records under moderate spring pressure covering 99% of both sides of the record labels. Didn't help warpped records one bit.
As far as putting too much pressure on the turntable bearing , I wouldn't worry about that. Newer turntables have the same kind of ball bearing washer as the old record changers had which stacked up to 12 LP's. As long as the clamp doesn't weight more than a stack of 12 LP's, there is nothing to worry about. Heck, I've got an old QRK, like a Russco, which uses a single large ball bearing at the bottom of the center shaft which is mounted to a 5 pound aluminum platter. Of course it's rim drive and has a huge Bodine motor driving it. Start-up time is less than 1/2 a second.
If warpage is your problem, either buy or make full sized record clamp discs, clamp a record in it, heat it in the oven, let it cool down slowly to room temperature and now you have a flat record!

 

Hifi record clamps aren't designed to address warps at all, although peripheral clamping rings and things like the Sota vacuum hold-down system to have that side benefit. But the whole thing with clamping isn't about warps.

Clamping is all about reducing and terminating vibrations of the record itself in response to mechanical movement and stylus velocity, and the noise and time-smearing and frequency bloating effects of those vibrations modulating the stylus/cantilever movement.

How well or whether they'll work in any given system has to do with the whole system design of the table -- platter/mat material, platter bearing, suspension and the clamp itself. It could be that in a given situation all that you'll do by clamping the record more tightly to the mat and coupling it to the spindle will increase noise from motor and bearing rumble, acoustic breakthrough, etc. Or if you're adding a weight that you're stressing the platter bearing.

I'm not sure I'd be looking to clamp a record to a lightweight aluminum platter or a bouncy rubber mat; I'm also not sure if clamping via spindle with a direct drive deck if the motor is directly coupled to the spindle, would be better or worse, or if every clamp design would be the same there, I'd think you'd need to try some kind of decoupling between the clamp's contact with the spindle and it's contact with the record (probably a good idea w/ belt drive tables too). I have a Merrill Heirloom that's designed with a lead damped acrylic platter, a screw down center clamp and a peripheral clamping ring and it all works great. But I'm not sure I'd be looking to try the same thing on, say and SL1200.

I don't know about the platter material, mat material and drive scheme of the OP's Denon, but those are factors to consider I think with clamping.

 

Interesting, I apparently had mistakenly thought clamps were intended to just keep the record from slipping so that it would stay in perfect sync with the revolution of the platter, but maybe that is not really an issue. I use a weight, which I assumed had the additional benefit of keeping it tighter to the mat for reduced noise, etc as described above.

 

i use a weight...

 

Because of the above I saw merit in Michell's approach n isolating the record from the platter, especially in a DD table. Those who expressed concern that the record is not touching the table I ask 'why should it?' as long as it rotates at the platter speed it is all that is needed and the clamp ensures that that is so.

 

My personal experience in this field is that all depends, and using a clamp or weight aren´t necessarily better in any way than not using them.
Mostly it will depend on the properties of the mat is in regards to damp the record. So the friction and damping properties of the mat should fit the vibrations of the record. Usually a rubber mat, rather soft, works best on its own IME.

 

I've got the Clearaudio Concept Clamp, which is really a weight. Aesthetically it matches the Concept turntable, not surprisingly. The clamp seems to help a bit with resonance and gives a very slightly "tighter" sound, but it doesn't make a really significant difference. If you're expecting a night-and-day difference, don't bother. Incidentally, this type of clamp would not help at all with warps.

As it was designed by Clearaudio to go with the Concept turntable, I can't imagine it would have any detrimental effect on its motor or bearing, but who knows. I do not use any sort of mat.

 

Pardon my ignorance, but what turntable is that?

 

Looks like a Pro-Ject Xpression.

 

Well the record needs to be supported and damped, if the record is not touching the platter and not supported along its entire surface, it's not very rigid to begin with, it's gonna be flexing like crazy, you'll have all kind of extra vibrations modulating the stylus movement and probably rapid continual changes in tracking force. Seems like a really bad idea to me. And I don't think that's the way clamping systems with center washers are actually designed to work, I think the washer is there to ensure that the clamp doesn't push down so hard at the center that the record is make to lift up and the outer edge when a platter or mat has a recessed center area for the record label. The whole point of clamping is to tightly couple the record to the surface beneath it, not to decouple it or lift it off the surface.