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groovegrunge
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Record Clamp recommendations for Denon DP-47F

Hello All,
I haven't visited this forum in a while. I was wondering if anyone had any suggestions for a Record Clamp for my beloved Denon DP-47F.
I trying to find a record clamp that fits the following criteria: a)Won't strain my turntables motor, b)Allows me to close the dust cover and c)Won't cost me a fortune(It's tough being an audiophile on a tight budget).
If anyone has some suggestions I would be glad to entertain them.

Many thanks;

Buddha
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Re: Record Clamp recommendations for Denon DP-47F

This one:

The Maplenoll and the Sota rule the waves.

Best wishes!

mrlowry
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Re: Record Clamp recommendations for Denon DP-47F

Buddha-

I'm not a turntable expert but is it advisable to use a record clamp with a direct drive turntable? I would think that the last thing one would want to do would be to more strongly "couple" the record to the spindle/platter which is of course DIRECTLY attached to the motor (the MAJOR source of vibration.) I'd think that "decoupling" with a upgraded record mat would more be in order. Plus may be some spikes to help drain vibrations out of the 'table.

Thoughts?

Jan Vigne
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Re: Record Clamp recommendations for Denon DP-47F

If I remember correctly, the DP47 is a direct drive table and I would also discourage coupling the main spindle to the LP to the stylus.

What is the op trying to achieve that a record clamp would solve? If it's "better sound", then the Denon leaves few options.

KBK
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Re: Record Clamp recommendations for Denon DP-47F

clamping the record will drop the overall noise floor. Long story. Whether it is DD or belt.

It will drop it in two ways, transfer and micro jitter in speed, caused by backward motion of the record on lateral shift of the stylus. This leads to better delineation in the dynamic envelope, besides the effect of correct and large peak transients. The two work together.

This is the one of the main reason that Art loves his massive rim drive Thorens 124: Massive instantaneous torque. Which is CRITICAL. rubbery mats damage that effect, to some degree, and felt decouples but kills dynamic expression via micro-cogging on the stylus lateral shifts.

Which is why many folks like the ringmat. It grabs just a bit better.

Clamps work quite well, viewed through the correct eyes. But I can't put one on my LP12, the suspension won't handle it. Not designed for it. Pity.

Jan Vigne
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Re: Record Clamp recommendations for Denon DP-47F

I understand the function of a record clamp. That's why I asked what the op's intent would be. If the clamp is intended to flatten warped discs, then that is one thing. If the op expects certain sonic improvements to be gained by the addition of a clamp to this turntable, then that is quite another issue.

I would still contend a record clamp on a direct drive table of modest book cost is not going to accomplish the desired results. Why? First, if you are going to make the case for better clamping to the platter, then you must consider the platter in this case to be the extension of the low cost motor in this DD table. As such, it has inherent flaws in noise and micro-speed control that canot be overcome by the addition of a record clamp. Indeed, the case is being argued the clamp will only make matters worse. If you are more completely coupling the disc/styus to a motor that has these noise and speed deviation issues, then the benefits of a more complete coupling are irrelevant if not totally counterproductive.

Noise floor is not likely to drop when you tightly couple the disc to the motor, that is the raison d'etre for belt drive tables. If it wasn't beneficial to decouple the motor from the disc, Vilchur would have closed up shop in 1959 and Ivor would still be working at a used tire shop still thinking and still hoping for his big break.

Let's say none of the speed or motor issues do exist and consider the other results of more closely coupling the disc to the platter (mat) of this table. The DP47 was a basic Japanese DD table, as such it had a typical Japanese DD table's hard rubber, ribbed platter mat. Experimentation is always the key to improvements but I wouldn't be betting that particular platter mat is what you want to clamp a disc to. The hard rubber doesn't hold the disc securely so micro-speed resolution is doubtful and it has pockets between the ribs where trapped air will create resonances the clamping action will only exacerbate rather than remove. The platter itself is prone to ringing when excited - excited, say, by a cogging motor. A more complete coupling to a ringing platter and a resonant disc surface that allows micro-deviations in speed will provide what benefits? Are these not isues the Ringmat was designed to eliminate?

I'm not sure what the Thorens reference means in this context. Yes, high torque on demand and the heavy flywheel effect of the massive Thorens platter would be benefits of the Thorens design but neither advantage is to be found in the Denon, quite the opposite in fact is present in this table.


Quote:
Clamps work quite well, viewed through the correct eyes.

Once again agreed, but you must view the Denon as a table that embodies many of the low end, mass market features the high end turntable market has stepped away from. As a product, the DP47, with its automatic functions tied to the tonearm, could be the poster child for all that was wrong with most mass market turntables in the waning years of Japanese table design.

Before the op searches out a record clamp, I would agree the Ringmat or suggest even a cork platter mat would be more beneficial. Without a clamp, even a felt mat would be superior to the O.E.M. issue. However, on the whole the DP47 still leaves little room for improvement and remains what it is, a low to mid-priced, two decade old, mass market Japanese direct drive table with a boxy frame and a not very good "S" tonearm with a detachable and highly resonant headshell.

Not to insult the op but tweaks to this deck are somewhat like hotrodding a 1984 Chevy Nova. The platform just isn't worth the effort compared to starting with a superior product and working from there. If this is where you are beginning with analog, then use the table until you can afford better. But save your money and don't get serious about changing the overall sound quality of this turntable. Investing more than a few dollars in a better isolation system is probably not money wisely spent.

(A DIY platter mat can be constructed from a stiff sheet of artist's watercolor paper and a dozen or so cork dots from the hardware store. Buy cork in a thickness that will not radically alter the vertical tracking angle of your cartridge/stylus, the end product should be approximately the same thickness as the Denon O.E.M. mat. Cut the paper to size and punch out the spindle hole. Arrange the cork dots in an undulating pattern across the paper, leaving a slight bit of free space at the inner and outer edges to accommodate the record label and outer lip. Using this in place of the O.E.M. mat will very likely result in a more "organized" and lively sound that the original mat provides.)

Buddha
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Re: Record Clamp recommendations for Denon DP-47F


Quote:
Buddha-

I'm not a turntable expert but is it advisable to use a record clamp with a direct drive turntable? I would think that the last thing one would want to do would be to more strongly "couple" the record to the spindle/platter which is of course DIRECTLY attached to the motor (the MAJOR source of vibration.) I'd think that "decoupling" with a upgraded record mat would more be in order. Plus may be some spikes to help drain vibrations out of the 'table.

Thoughts?

I'd call it a trade off between the benefits of the clamp vs, the detriments of more close association with motor issues.

For the direct drive tables I've played with, I prefer to change the stock mat and use a clamp. (Almost like creating a constrained layer beneath the stylus.)

I even thought the old grey felt mat made by I-forget-who with a clamp made for a pretty noticeable improvement.

We could ask the same clamp questions for other turntables, as we are putting weight on the spindle and increasing noise and friction that way, too.

Jan Vigne
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Re: Record Clamp recommendations for Denon DP-47F


Quote:
We could ask the same clamp questions for other turntables, as we are putting weight on the spindle and increasing noise and friction that way, too.

Only in a few designs might this be the case. Most manufacturer's clamps are a screw type or an actual clamping type that would add little if any downward pressure or weight on the spindle bearing. A record weight would be a different issue. Anyone know of any company recommending record weights nowdays? I don't unless you count the VPI peripheral clamp.

groovegrunge
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Re: Record Clamp recommendations for Denon DP-47F

Hello All,
I would like to thank you all for your contributions. I would also like to clarify the purpose of my question. My intention was to acquire a clamp to flatten warped records. My thinking is that flattening a warped record would make the job of cartridge(Shure M97xE)much easier therefore making an improvement in sound.

Jan Vigne
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Re: Record Clamp recommendations for Denon DP-47F

I seriously doubt you'll be able to find a drop on weight that has sufficient mass to actually flatten a warped disc. If you do, it will very likely be so massive it will cause motor/bearing problems. Check with a retailer such as MusicDirect asking for a reflex clamp of some sort.

http://www.musicdirect.com/product/74432

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