SSM w/Rim Drive - Cloud 11 Vibration issues?


I was wondering if any other members have run into a vibration problem. I upgraded my SSM with the Rim Drive. I also use the the Cloud 11 vibration control system. The Rim Drive is creating vibration to the 11 platform. This creates a slight wobble to the tone arm. VPI was extremely helpful and they are sending new motor mount feet. They aren't sure that this will fix the problem. But they state that the new feet will give a little to the vibration control. Has anyone else experienced this problem? If so, what coarse of action did you take to compensate? Thank you in advance for your input!
zenieth
Hi Zenieth,
I also have recently changed to the rim drive and formerly used a cloud 11. Mine was called the cloud 11 when I bought it but now is called the Cloud 12. It is the two piece model with separtate motor platform. This two piece definitely won't work with the rim drive. If yours is a single piece it may work better but I suspect there will still be to much movement. Better to have a more solid and well leveled foundation. My solution was to order the master platform from Critical Mass Systems. Less expensive would be a three inch thick Maple platform. Chris at Timbernation.com makes these at very reasonable prices. As much as I like Vinh and his Gingko products, I don't think they were designed with anything like this rim drive in mind. I highly reccomend his dust covers if you don't have one already.
The softer feet that VPI will send will likely make a big differnce. I'm waiting for mine too. In the meantime on a reccomendation from Stringreen, I have attached adhesive felt pads to the motor housing feet to gain similar effect. This has helped already with mine as well as just giving the unit some run in time. I think the drive belt smooths itself out with use.
Mike at VPI told me they're working on a softer drive belt as well which will be available in a couple months at no cost to rim drive customers. This should make things even smoother. So for I am impressed with the grip and control the drive provides. Its more work to implement than the belts but I think it will be worth the trouble. I haven't enen been able to play music with mine yet because my GCPH is out being modified by Cullen Circuits.

Good luck and be patient.(The rim drive likes to barely touch the platter for best results. I've found that if my super platter spins just slightly longer than the flywheel on shut off but still starts up smoothly it work the best)
Agreed, the rim-drive motor/flywheel assembly and the TT plinth should rest on one slab in order to fix the geometry between the two. Any play between the motor/flywheel assembly & the platter will compromise speed stability.

You could fix things and preserve the benefits of decoupling from earth via the Cloud platform, by elevating an oversized wood or slate slab on top of your existing Cloud base. Slate would do the best job of absorbing motor vibration. Cones could be used for elevation, or perhaps the new slab could simply replace the top of the Cloud.
This is an E-mail I sent to VPI with Harry's answer regarding the rim drive

Date: Fri, 30 May 2008 10:50:55 -0700
From: [email protected]
Subject: Re: Suggestion
To: [email protected]

Hi Stan, it's interesting that with the belts you need everything solid but with the Rim Drive you need a small amount of lossiness on the feet of the motor assembly. If you have any sorbothane or thick felt or anything that has a bit of give put it beneath the feet, it will solve any problem like this. Try it, you'll see.

HW

Stanley Green wrote:
Hi - I have a Superscoutmaster, 10.5i, with a new Rim Drive that you helped me with. I'm hearing a speed inconsistency now that I never heard with the belt drive. I lubricated the motors and the turntable, but that didn't seem to help. The numbers in the SDS don't seem to be inconsistent. The out of tuneness is a slow kind of wavering. Do you have any suggestions?? Thanks Stan Green
Stringreen,
It sounds as though the felt or sorbothane has pretty much smoothed your SSM out. Did you order a set of the softer feet or are you satisfied with what your using. Mike at VPI told me this week that they are designing a softer O-ring to use as the drive belt that should smooth out the drive even more with or without softer feet.
These posts suggest that there is a significant amount of noise & instability generated by VPI rim-drive motor/flywheel assembly. It would be interesting to compare this to Teres rim-drive, which is allegedly a quiet motor. Sayonara.
I am actually using a soft gummy kind of material that once was a mouse pad. Naturally, I tried many different materials, but this was better than the felt. I am very happy with my rim drive setup now. It is far better than when the belts provided the power.
Dgarretson,

It sounds like noise has been the biggest drawback of any rim/direct drive mechanism. I don't know much about the Teres drive but I'm sure they've come up with their own set of solutions. I also feel that with the use of the flywheel the VPI has great potential to be a smooth and low noise drive system. Figuring out the optimal setup is the challenge as with anything else but I think the rewards will be worth the trouble. I still have my belts handy but I'm not planning on using them again anytime soon.
Harry told me that Pearson thinks the Superscout with the rim drive is fabulous. There is a review of it which hasn't been published yet. I suppose when these "little bugs" get exterminated, they will run the review.
Wish they'd come out with the single motor/flywheel combo version of the rim drive.
Also wondering if I'll have to change my isolation (assuming they do produce the rim drive for mine). Now the motor sits on a platform raised slightly above the Gingko. Hoping the slight give of the Gingko will negate the need for softer feet on the motor. Really like the Gingko under there.
I think everybody needs to wait until Harry comes up with the 'third' generation version of the 'rim'. By then, all the bugs will be out, hopefully. Until then, the 'fly' will be the way to go. When the third generation comes out, it will have a custom motor platform and table feet will be matched to the platform for height and damping. Until then, the mod is just not cost effective for the sound it produces. Also, I will not be surprised if Harry comes out with a complete rim turntable, arm and motor. Say, $8K. When you engineer it as 'system' results are always better.
I don't doubt that the speed stability of VPI's rim drive improves upon standard belt drive.

Aiming for the correct amount of compliance in a drive system is probably an elusive design goal. With the 300RPM motor on a TNT, I heard significant improvement using a carpet thread-- which has much less compliance than VPI's soft rubber belt. But performance audibly degraded when I tried virtually inelastic Stren braided fish line. The complete lack of elasticity requires that the fish line be tensioned very tightly to grip. It pings like a piano wire and transmits all AC motor vibration to the platter.

From what I can gather, part of the problem is vibration inherent in any AC motor. There needs to be at least some minimal compliance (or "lossiness" as stated by HW) in the drive train to absorb it. In rim drive, noise at the contact point between the driving pulley and the platter introduces additional noise. I believe HW mentioned on AA that the surface contact noise of his rim drive was reduced by using a large-diameter driving wheel. If this is true, then his approach would seem to be preferable to the small-diameter O-ring/motor pulley used by Teres. HW's email suggests that they're looking for softer materials to improve in this area, and also perhaps to improve grip at reduced pressure from the driving wheel.

On the other hand, the quieter DC motor used by Teres would seem to be a better choice for rim-drive. It introduces fewer problems to solve, requiring less compliance(slop) in the drive train than an AC motor. Less compliance = tighter coupling = >speed stability.

It remains TBD which system sounds better. However, VPI's retaining soft belts between the motors and flywheel looks like a kluge approach. While fooling around with thread, I found that even the short rubber belt between VPI motor and flywheel sounded slurry relative to low-compliance thread.

Another way to tackle the AC motor noise issue is through the speed controller that governs the 2-phase AC motor. In this regard I think Mark Kelly's AC-1 controller is something of a break-through: it allows voltage (and other paraments) to be separately varied for each phase of the AC motor. With some tweaking, you can virtually eliminate detectable vibration from the 300RPM motor. In constrast, an SDS(or Walker) cannot do this. With the VPI two-motor cassette, the situation is further complicated by the random phasing activity of two unsynchronized motors.

Of course it's about implementation, not just theory.
Thank you for your responses. I tried some felt substance pads under the feet. I then removed the Cloud and put the table on a granite base. The problem is non existant and the table sounds great! I guess I'll have to make a decision whether to go back to the Cloud or be happy with the granite.
Zenieth,

My phono stage finally came in and I was able to play my system with the rim drive after having stabalized speed for about a week without music. The table sounds great with no indication that the rim drive is causing any problems or noise. Break in and attention to set up make all the difference with this drive. My guess is you should leave it on the granite. Mine's working great on maple while I wait for the Critical Mass platform to be completed.
I hope nobody has been discouraged from trying the rim drive by the dicussion of these "bugs". I can tell you they are minor and easily compensated for. If VPI does come up with a tweak upgrade or next generation I'll likely get in line for one. Until then it's really quite enjoyable as is.
My replacement feet showed up from VPI. They are a much softer material. They are much taller than the original stock feet. I haven't went back to the Cloud since the granite is working well. I do believe that the new feet would raise the motor drive considerably. This will create a problem since the Rim Drive needs to run in the middle of the platter. This wouldn't work unless you raise the table so that the rim can drive where it is suppose to. Then there is the issue " how do you raise the table on the Cloud 11? The table's own adjustable feet wouldn't be able to raise it high enough. I guess, I'll stick with the granite base.
My replacement feet arrived also and I would agree that they raise the motor higher than I would like. I tried them anyway and raised the table accordingly.(This may be easier for me since I have the mini feet) They do work well when set up this way but probably no better than with felt pads under the original feet. In fact, there may be a slight loss in livliness. It's a simple matter to switch back and forth if you're so inclined but if you're happy the with the way you have it, you may just want to leave it. I'm looking forward to trying the softer drive belt as this may obviate the need for softer feet.
Sonofjim, I believe that I will leave it on the granite base. I could have better bass than I currently have. I'll drop the rear of the arm later and see if that does it! I would have interest in trying the softer belt too. I have a slight noise in one motor. When I remove the ring clamp it goes away. I wonder if this will go away as more play time is accomplished? I never had the noise before I installed the Rim Drive. It's not loud enough to diminish sound but I know it's there. Any input?
If the noise seems to be coming directly from a motor it could be a problem with the motor. I think there's capacitor in the wire path to the motors that can drift out of synch somehow. Mike at VPI told me something about that. When you reverse the wiring it could introduce coginess to that motor. In that case, I'm sure VPI would send you a new motor. If the motor seems to be the source I would conact Mike. He would understand it a lot better than I do.
I would try to make sure that it's not drive belt noise by moving the motor assembly away from the platter. If your noise stops, try lighter conact of the drive belt with the platter and this will decrease or stop with time. Also you might try removing the belts from the motors and watching them run freely to see if one is more jerky than the other. Mine is running smoothly with barely notable motor and contact noise.
I hope this helps. I don't consider myself an expert on this, or anything really, but this is what knowledge I've gained from my experience so far.
Absolutely, you can contact Mike, however, to put your mind at ease, I had some motor noise when I first installed the rim drive, but it's now gone. I really can't remember, but I think it went away about the same time as I used the softer footers.
I actually ordered the SSM with rim drive and a cloud from music direct last week. should I tell them to hold off on the cloud and just use the 2 pieces of 14x18 granite i'm currently using under my linn that are sandwiched between a piece of mdf and which are both sitting atop my billy bags pro 35 turntable stand or should I set it up differently when it arrives?
Powerdoctor,

I like the Cloud products in many respects and I doubt there's a better guy in the audio industry than Vinh. However, I'm afraid there may be to much movement of the plinth-platter assembly when using the rim drive on these pieces. I didn't even try it with my 2 pieced unit. A one piece may work better but, based on Zenieth's experience, I doubt it's optimal. You could try it if Music Direct is willing to take a return. Something more solid like your granite is probably better(more solid isolation like Silent Running Audio, Critical Mass, Symposium, or even maple are other options) It seems like you need slight play in the motor housing but not the plinth(soft footers and in the future softer drive belt).
Once you get this thing set up and running you will enjoy it thoroughly. Have fun.
I just took delivery of a medium size Cloud 11 for my SSM with Rim Drive. It replaced a standard size version which was fine for the flywheel edition of the SSM. I've experienced absolutely no speed variations (piano/cello) or vibrations as noted in the above posts. I (and Vinh Vu) agree that the two piece version is not suitable for the latest SSM due to the resistive nature of the rim/platter relationship.

My Cloud 11 sits on a 2" maple platform supported by 2" brass cones, resting in a maple rack. What I did do differently was to place the Gingko balls in 9 of the 10 pockets available on the base. I left only the one slot open - the middle row to the left of the far right edge. This is a massive unit and the five balls supplied as standard just won't support the top piece properly. Vinh is now going to start supplying 9 balls for this revised SSM configuration, and I would suggest trying it with any SSM version which has the Super Platter installed.

Finally, Gingko is now producing a ClaraVu dustcover for this combination which has proper openings in the rear and proper height (to accomodate 10.5i and it's Nordost wiring) for the latest and greatest SSM configuration.

Three last notes: 1) Harry, please give us at least six months to recover from your latest upgrades!; 2) my SSM has the HRX footers and standard footers for the motor assembly; 3) I agree with the poster who suggested having the rim barely touching the platter - you'll experience a delay in the rotation of the platter when set properly.
Vinh Vu of Gingko Audio here.
To accommodate the new Rim Drive, we are offering a 1-piece Medium Cloud 11 that would work with it, as Cmaronmurphy atested here. We also offer a matching SST table top cover to fit perfectly on the Cloud.
Those who have the 2-piece Cloud designed for the original SSM and wish to trade it in for the 1-piece Cloud, please contact us through our website.