Dynavector 17D3 hitting clamp on VPI Scout


Hi, everyone. I've got a serious problem with my new Dynavector Karat 17D3. It was professionally installed and set up on my first-generation VPI Scout table with the JMW tonearm. It works fine until the stylus goes into the blank grooves at the center of the record. Then the side of the cartridge hits the VPI record clamp. Aside from the loud crashing sound this produces, the dealer says that the impact may damage the stylus. For the moment, I'm playing records without the clamp. That's not really a good solution, though, since the clamp performs an important function and is recommended by VPI. Have any of you encountered this problem? Any tips for a solution?
madcitygeoff
This would seem to be a problem with only certain LPs that have an unusually broad playing surface, so the run-out grooves run under your clamp. Is that the case? The Karat has a very delicate and tiny cantilever (which is what will get damaged before the stylus per se gets damaged), so I think you have no choice except to eschew use of the clamp on LPs that exhibit the problem. Unless you want to risk your expensive cartridge....

Maybe you can find an alternative suitable clamp with a narrower base, or take your VPI clamp to a machinist and have him grind down the periphery a bit.
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Thanks for the replies, folks. Lewm, I'm not positive, but I suspect that the problem will occur with most if not all records on my system. I only played a few before I realized what was happening, and since then I've either lifted the tonearm before the run-out grooves or played records without the clamp. I don't want to do any experiments that might cause damage. I checked the records I played, though, and the clamp doesn't extend over the run-out grooves. I checked a number of records by moving the tonearm by hand to the end of the playing surface (without actually playing the record) and it looks like the edge of the cart would impact the clamp in every case. The problem seems to be that the cart is wide enough that its sides extend beyond the playing surface.

I like the idea of grinding down the clamp, although I don't think it's going to work. I looked at the bottom of the thing and discovered that the surface is only about a quarter of an inch wide. If I ground it enough to give room for the cart I might destroy it.

I'd be open to using another clamp or weight or something. I'm very new to this so I'm not really sure what the options are. It looks like most of the clamps out there are for specific turntables.

Thanks for helping out a newbie!
Another newbie question.... do turntable mats perform some of the same functions as a clamp? Would a mat be a solution in my case?
I found the same problem with a Michell Engineering clamp. The Karat 17D3 has a very wide body and it hits at least half the LPs that I've played. I try to lift the tone arm before it hits the clamp but oftentimes I'm just a tad late. I don't think that the slight bending of the cantilever is exerting enough torque on the stylus or generator to do harm in the short term but I've been thinking of shaving the clamp down to avoid potential damage in the long term. The Michell Engineering clamp bell is made of delrin so it'll be easy to grind down but I'm not sure about the resulting aesthetics.

Seems that Dynavector needs to redesign the Karat's dimensions so that it doesn't become a deciding factor in cartridge choice. The 17D3 is such a fine cartridge, I'd hate to think people would avoid it because of this problem.

Tom
Hi, A mat won't solve anything for you. It also requires raising the tonearm, to maintain proper vertical tracking angle and stylus rake angle. I have a Dynavector XX2MKII cartridge, and have not had any problems such as yours. I have used the clamp that came with the table, the Stainless heavy VPI weight, and now a TTW (Turn Table Weights) heavy brass clamp that works very well, and is a joy to look at. I don't recall anyone else having this problem, and there's quite a few Scouts out there using the same cartridge as you are, so I am surprised to hear this. If it's a newer version of the Scout, perhaps they changed the clamp. Try giving VPI a call, and report the problem, I'm sure they can come up with a solution.

Good luck,
Dan
Perhaps I am misunderstanding you. Clamp goes on top of LP; mat goes under LP. Two different functions and different relationships to the LP.

Yes, as I recall the VPI clamp is not particularly large in diameter, so I don't quite know why you are having this problem, unless, as you say and as Elizabeth may be suggesting, the DV Karat is very wide body. I just recently set up a DV Karat for a friend and did not notice that.
Thanks for clarifying the mat issue. VPI is aware of the problem but I haven't heard anything from them yet. I'm trying to do some self-education in the meantime.

I did a bit more research and found a product--the Rek-O-Kut Disc Stabilizer--that was specifically designed for the problem of record clamps hitting the cartridge. It's a lot narrower than the VPI clamp that came with my Scout--2-5/16 inches vs. 3-1/2 inches. It's a weight and not a screw-down clamp.

I'm wondering if this product would be appropriate for my Scout. If so, would I use it in conjunction with the washer that VPI supplies for use under the record?

I really appreciate the help that you're all offering. I'm learning a lot here.
Geoff, not sure it's a problem with the clamp(s) so much as it's a problem with the wide body of the 17D3. The Michell clamp is a similar width to the VPI at 3.5"/87.5mm, which is a very common record clamp diameter.

Record weights are ok but I prefer to use the relatively lightweight clamps that Pro-Ject, Michell, VPI, and others provide. A record weight has to be heavy enough to provide the same amount of pressure as a clamp and so puts additional weight on the platter bearing. When a platter bearing is designed for a heavy weight there's no problem, but when a platter bearing is not designed for the heavier weight there can be additional wear on the bearing itself. The amount of wear may be negligible but I'd rather not find out after a thousand hour of record play that I have to replace the platter bearing.

I haven't done an exhaustive search for a lightweight clamp with a smaller diameter bell (perhaps 85mm would do it) but so far I haven't found anything. If you come up with something in your search, please post. Otherwise I think a visit to a machine shop is in order.

Tom
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I did a little more research and found the KAB Record Grip Mark II, which is a clamp and not a weight, with a diameter of 3", a half-inch less than the VPI clamp. That extra space might be enough clearance for the 17D3.

Thanks again to everyone for all your help!
On the subject of mats/clamps, I am using a TTW copper mat, with the heavy brass VPI TTW clamp. To get the clamp to work with the mat, I had to modify it by grinding down a 1/4" 20 nut to just the right size, and pressing it into the clamp, to make the threads extend down far enough to enable tightening the clamp on the lp. I then squeezed the VPI washer between two steel plates to the proper thickness and baked it at 300 degrees for about 25 minutes. It is just the right thickness. The TTW clamp has a concave radius on its bottom side, so when the clamp is tightened, all but the very worst warps are flattened out and playable. A very important benefit is the solid contact now between the bottom of the lp, and the Mapleshade Integrated Record Coupling System, which concentrates the area of contact to three points on the copper mat. This helps to drain vibration into the mat(s), which has made vinyl playback have a clarity I have never heard before from my table. This works, but feel I must be some kind of nutcase whenever I mention it, as no one seems willing to try it. Pierre Sprey may be eccentric, but he is not a nutcase, and the proof is in the listening.

Yours in music,
Dan
I have a VPI "Classic" and experienced the same problem as the OP. I have a TTW lightweight stainless center weight, a TTW copper peripheral ring, and I have an Ortofon A90 cartridge mounted. I also have a Boston Audio Design mat. In my case it was the headshell that ended up hitting the center weight not the cartridge, but the result was the same; probably the worse noise I have ever heard come from a turntable. As it turns out, I decided I prefer the sound of the table without the center weight, but absolutely, no question, prefer the set up with the periphery ring.
Dan, I wish I had your patience and mechanical skill. If I attempted a project like that, I'd either cut off a finger or burn down the house. I'm afraid I'm stuck with commercial solutions for now.

On the subject of weights and possible damage to the platter bearing, I see that VPI makes a weight for its own tables. I assume that means that the Scout could bear the extra weight with no problem.
Geoff, I have made that assumption. As long as the bearing stays lubricated, I believe it to be plenty stout enough to handle the extra weight. Between the copper mat and the brass clamp, it's probably close to an extra five pounds it is supporting. All I know is the sound from the Scout is astounding to me now, I feel I have finally fulfilled the promise that vinyl offered, but eluded me for years, until I figured out how to unlock the secrets to fulfill that promise. Whew! At last!

Best of luk,
Dan
Years ago I used a Clearaudio Gamma, a very wide cartridge that did the same thing on my HW19III--I special-ordered a one-piece clamp from VPI- it looked like they ground the outside of the tapered perimeter of the clamp-problem solved. There is still about 1/8" of material around the perimeter that actually presses down on the record. I've used this clamp for 8-9 years now with no problems; of course I'm using a different cartridge now.

I do think the machine shop might be the answer, or you might call VPI for their recommendation
Hi Madcity i have the same problem as you, so instead of changing or up grade to a Furutech Monza which is 3" dia vwhich work fine vs new dyna xx2,
i think your choice is much better. i have tested the Furutech monza very little improvement
i have 60 hrs on my 17D3, may i ask how much improvement you get, and what is the different price you pay.
thanks
Chris
I've heard of this problem a few times. If you send your clamp back to VPI, they will take a sliver off of the periphery. Problem solved