[Baumli]

Dear folks,

As many of you know, our member, Gabe Batson (of Tufts and Batson) not only works with Amelia in making great fly rods, he also is very proficient with other creative immersions. For example, he made some wooden turntable weights for me, one of chen chen and one of cherry, plus he modified a maple one I had. They worked out great, and the one made of chen chen is just gorgeous.

Having once heard a Shun Mook clamp, I have always wanted one. (Yes; I know it actually isn't a clamp, it's a weight, but the makers called it a clamp.) However, I'm not going to pay the price they now go for--on the used market only, since they are no longer made. The fellow whose unit I heard paid a little under two grand for his, and sold it because he could get $3600 for it! That's a lot of money for a center weight!

But I would be satisfied with a clone, made of ebony, even if the ebony is not quite up to the quality of wood the Shun Mook was made of. I've of course seen it once, had my hands on it in fact, and I've seen many pictures. But I would like to have the dimensions for the thing, so I can give Gabe some directions other than just a picture. Is there anyone in our vicinity who has one, and would be willing to measure it carefully, and share these dimensions?

I would very much appreciate any help someone can give.


Thanking you from the
depths of my audio fixation,

Francis Baumli

[FullRangeMan]

Shocking, hard to believe that anyone would pay such a large sum for a so simple product.
I dont know the dimensions you ask, but I can say the orginal wood ShunMook used is not the ideal wood for the task, since its a hard wood.

I suggest you made some pieces from various soft woods and choose the best sound. Important: the wood must be very dry.

What dimensions? Use round shape in the Golden Ratio proportions (1 x 1.618).
Do you would post any photo from your clamp?

[Scott F.]

Hiya Junior Member

Although I don't have a clue want the dimensions are to a Shun Mook clamp, it looks pretty easy to build. Tell you what, I've got a lathe and all the knives needed to turn just about any design you could come with. There are some really cool woods that you could turn and make some stellar looking record clamps. The one wood that comes to mind is Lignum Vitae. They use it for cricket balls because it is so dense and heavy. Its a little on the pricey side but it is so dense that when you sand it using 1000+ grit sandpaper, there s no need for lacquered finish, it comes out that shiney. It dulls knives and blades like crazy but it's a cool (extremely) hard wood.

That said and as usual, time is my enemy. I'm not sure I could find a free day that the two of us could get up to the wood shop and crank a few different varieties out. But, if you don't mind picking up some turning stock then playing it by ear, it would make a fun little project. 

Toodles....

[FullRangeMan]

If the original ShunMook is a hard wood it not work as a filter, but as a resonator.

[audio.bill]

I have no connection with the following seller or the product for sale, but thought it might be of interest in this thread. It appears to be a knock-off of the original - http://www.usaudiomart.com/details/649197070-ebony-record-clamp-compare-to-shun-mook/. The ad shows a price of $999, but states that if the wooden storage box is not needed he is open to reasonable offers. I also found the actual Shun Mook is apparently still available for $2,800 from The Cable Company http://www.thecableco.com/Product/LP-Record-Clamp.

[FullRangeMan]

I suggest this shape in the Golden Ratio dimensions:
Wide diameter: 100mm  Hi: 60 or 62mm.

[Baumli]

Dear folks,

Thank you for your several replies, and generous offers.

Scott, I would be tempted to take you up on a day spent turning some different center weights, but you know as well as I do that it could take us months to find a time we both could do it, given the distance between us and the fact that we both work over 60 hours a day. Still, down the road, I may take you up on this.

I'm still tempted to have Gabe give a go at a center weight, although once he has a look at an original Shun Mook he may feel deterred. That original SM weight isn't just made of ebony; it's made from the ebony root (sic!) of aged ebony that has been dead and marinating in swamp water for over 100 years! Is it now dry? Or is it like the oils on paintings dating back to the medieval period--as early as Giotto, which still aren't completely dry?

I become depressingly aware that most people haven't a clue as to what a center weight is actually supposed to do. It should do three things. One is hold the record in place so it's more steady. This is the only function most people know about. Second, it is supposed to pick up the resonance from the record surface, and resonate in turn, but not as the Shun Mook people say--which is to then pass this more tuneful resonance on to the cartridge. Rather, it should have enough mass to convert this resonance to heat and thus get rid of that unwanted resonance from the record's surface. The third thing it should do, and all wooden weights fail utterly at this, is serve as an electro-insulator between the spindle and the cartridge. The most serious source of unwanted noise in most turntables is EME being thrown (as EMI) to the center spindle, which then travels up that spindle, and gets spun out as a "field"--some of which goes to the cartridge. Insulate the tip of that spindle with, e.g., acrylic, and you accomplish this third function of a center weight.

But when one goes with wood: If that center weight did not resonate, it would not pick up unwanted resonance and convert it to heat. The question is, how much do you want it to resonate? And this often is dependent on the record itself--how hard the vinyl is, how thick the vinyl is, and so on. There used to be entire magazines put out by audio engineers on the merits of different vinyl compounds.

After driving myself crazy for years trying to find the best weight, the best material(s), and so on, I finally had to conclude that there isn't any best weight for the center weight because LPs themselves vary. I have, however, spent literally hundreds of hours experimenting with this. What I came up with were averages. I found that on average the best weights are: 10.3 oz., 11.1 oz., and 8 oz. exactly. In this order. I've found, so far, that the best wood is hard maple. I've found that #1 acrylic is slightly better than maple.

So now Scott throws a wrench in to my thinking by suggesting lignum vitae, knowing full well that the Latin name would get my attention and cause me to obsess.

So that's what I need to do some more. Obsess, then buy the wood, then decide who gets to suffer the indignity of dulled knives as I proceed with one more crazy project.

One last thing: Can someone please tell me what the "Golden Ratio" is? I know George Cardas uses it in his wire, and I used to know him personally, about 25 years ago before he became a recluse. I asked him way back then to explain it to me, and he said it is an industry secret. But obviously someone else knows about it. Why does this Golden Ratio have such co-called amazing properties? Is it somehow at the core of every building block in the physics that make up this universe?

I'll slowly come to a decision about which wood to use.  But any information on the Golden Ratio would be appreciated.

Thanks to all of you for your input on this intensive project and elusive concept.

All the best,

Francis Baumli

[FullRangeMan]

Golden Ratio is the Fibonatti sequence as taught in architecture school:
1 x 16,18 x 26,16 x 36,18 etc
Upon what human body, plant are made etc:
https://www.google.com.br/search?q=golden+ratio&ie=utf-8&oe=utf-8&gws_rd=cr&ei=LrLZVYS5CYqUwgT_5JOACA

That original SM weight isn't just made of ebony; it's made from the ebony root (sic!) of aged ebony that has been dead and marinating in swamp water for over 100 years!
This is a romatic banner from ShunMook to catch audiophools, nothing to do w/commercial timber sales.
If so how many swamp trees roots would to be need to supply LP clamps since release date from this vinyl clamp(1990s), tens thousands.
A tree root is obviously small just a small part is useful.

If you are able to find brazilian woods is your area I would suggest:
Mogno (soft wood)
Imbuia (hard wood but yet easy to handle)
Pau Ferro (extreme hard wood, difficult to cut, rare and expensive)
Used in boutique jazz basses as scale in place of eboni.
I have see Pau Ferro just once in this life.

Wood mentioned by Scoot F seems a nice suggestion.

[daves]

Pau ferro is normally in stock at Hibdon Hardwoods.

As far as shielding em/emf fields radiating from the spindle. A nice copper insert sheath would take care of that issue muy pronto, Francis, and Gabe could make a perfect insert with no problem.

[BruceW]

Hello, I use the Shun Mook Clamp--and yes it is as good as they say--while the price has spiralled out of hand they can be found on the S/h market--you just need to sniff them out

Well worth it though

Clones?-- maybe they work--

BruceW

[Baumli]

Dear gentlemen,

Well, this like most such forays, is turning into something complicated. I'll do research on the "Golden Ratio." Thank you for supplying the lead. I'll have to decide whether to go with that or with the shape of the Shun Mook. As for the weight being made out of the root--well, I had wondered about that. How in the world is the customer supposed to know? It's like when Raphael's sponsors would buy him pure lapis lazuli, and it would have to be tested to make sure it was pure. Only a very few people at the time could know, usually the painters themselves knew, but they were not involved in buying it.

And as for BruceW: I've seen these on the used market, but usually they go for much more than a new one. The old ones are supposed to be better--one more bogus claim? If you own one, can you supply its dimensions: both weight and also the bottom width, top width, and how high that place in the middle is where it tapers down to a more narrow width?

Your input would be appreciated!

All the best,

Francis Baumli

[FullRangeMan]

Iam curious about the weight from an these ShunMook clamps.
The Golden Ratio dimensions are as I informed:
Wide 100mm Hi 62mm according 100/1618=62
Preferably without moving parts.

[Baumli]

Dear people,

As usually happens in audio, matters quickly become complicated.

I already knew about the "Golden Ratio" as it is used in architecture, and about its visual and structural presence in nature. I also know about the "detractors" who point to the exceptions, and especially the variations: As much as 12% even in supposedly perfect instantiations of the Golden Radio, e.g., the snail shell.

What George Cardas considered an industry secret, and what I can't get any opinions on, is how this Golden Ratio would be expected to have musical benefits if used. In other words, what are its sonic characteristics? How does it apply to sound?

And as far as putting a brass sleeve into the hole of a tt weight, I've now talked with a materials engineer, a materials physicist, and my son--who took a double major in physics and math, and is an audiophile himself. No one had any belief that putting copper there around stainless steel would in any way shield the cartridge from the EMI. It might "split" the bandwidth, thus causing two different interferences to go to the cartridge. It might attenuate the EMI very slightly ("maybe at most 2 percent," the materials physicist opined) and he went on to explain all this in math I didn't understand, but basically it involved curving a small part of the bandwidth into a frequency the cartridge wouldn't be affected by. But this same fellow opined that rotating copper, or brass, might end up being a small antenna and actually increase the hash a very small amount. The materials engineer said in his opinion its only value would be to protect the wood from being "boogered up."

So I guess I have two questions? Why would a metal sleeve that small block any EMI? And, especially, what are the sonic or musical benefits of following the Golden Ratio?


Whupped by flaccid cogitations,

Francis Baumli

[daves]

Francis, if you want to replicate what SM did because of concern about the EME, then you need the copper cup.

Or you can run with non-ferrous materials for the platter and spindle and not have any concern.

Or you can have Gabe replicate the geometry of the cup with wood, and swap out the two forms at will, and enjoy both worlds.

As with all shielding, the copper spindle cup will not eliminate the magnetic field, but it will deform the intensity or flux of the field, and lower its possible intersection with the cartridge coil(s). Kinda like a fat man sitting on a pancake....the pancake is still there, but it's hard to get any syrup on it.

And almost all engineers hate anything to do with audiophile concerns, but still we obsess.

[FullRangeMan]

In other words, what are its sonic characteristics? How does it apply to sound?
So I guess I have two questions? Why would a metal sleeve that small block any EMI? And, especially, what are the sonic or musical benefits of following the Golden Ratio?

The sonic characteristics of Golden Ratio when proper apply in a room are a fully neutral and balanced sound, the harmonics are said to be, well golden.

When the room is double Golden Ratio(Golden Trapagon) the sound is even better, it have no parallel wall, Cardas said: The side walls become the strings and the end walls are the bridge and the tailpisce.
http://www.audiocircle.com/index.php?topic=107352.msg1183456#msg1183456

[FullRangeMan]

And almost all engineers hate anything to do with audiophile concerns, but still we obsess.

Engineers and mainly scientists are isometric people with a narrow understanding of the universe, they think this universe is mathematical, precise, constant and well, Digital.

But God has built this universe of a manner relative, variable, changeable, emotional and well Analogue.

[Baumli]

Gentlemen,
   I appreciate your several postings about the Golden Ratio and its sonic applications. George Cardas explained all this to me a long time ago, and I’ve heard music systems in rooms set up to replicate the Golden Ratio and also one room which replicated the Golden Trapagon. The results varied. One Golden Ratio room seemed just right, and sounded wonderful, even though it had a high-end system which would (if I may say) be at the bottom third of what a high-end system is. The two other Golden Ratio rooms I heard didn’t have anything special about them, and the Golden Trapagon room not only didn’t sound good it felt weird, looked weird, and just plain put one in a mood that was anything but musical or visually aesthetic.
   George Cardas had long ago explained the Golden Ratio “reasoning” of these rooms to me, and yes, he had explained how they mimic the structure of a stringed instrument. All this he was open about, but he was not willing to divulge how he applied the Golden Ratio to his wire, calling it an industry secret.
   But maybe George Cardas is prejudiced here. He is a guitar player. (And a very good one.) So he designed a Golden Ratio room which mimics the structure of a stringed instrument. What if he had tried to mimic an oboe, or a trombone, or a percussion instrument like a timpani or even a woodblock? Or, perhaps most difficult of all, a full-rank pipe organ? I don’t think he could have done the Golden Ratio math with those instruments!
   If there is anyone attracted to numerology as a means of explaining the structure (and sheen) of the universe, it is myself. But I note the imperfections of most objects in the universe, and as one commentator well put it, one has to conclude that our universe is analogue, not digital. (All this is metaphorical, yes, however I do think the point is made.)
   But this discussion is geared toward how to make a Shun Mook weight clone, or an even better weight than the Shun Mook by following the Golden Ratio equation. Frankly I am somewhat embarrassed as I proceed with this discussion and exploration. I waxed enthusiastic about how the Shun Mook weight was the best weight I have ever heard, and yet, in truth, I never heard it on my own turntable, in my own system, nor did I even get to compare it to a different weight on the owner’s turntable. Certainly it was, visually, the most interesting and pleasing weight I have ever seen. Were my visual faculties prejudicing my aural faculties? I rather suspect they were, because my exposure was not at all a discerning test of its merits compared to other weights, or for judging how it would sound in my own system.
   So what way to go? I am nearing a decision, keeping in mind that Gabe’s time and energies should not be exploited here, and also trying to make this approach work in terms of both physics and numerology.
   Dave’s comments are ambitious, but I am wary. He states that an inserted “copper spindle cup will not eliminate the magnetic field, but it will deform the intensity or flux of the field, and lower its possible intersection with the cartridge coil(s).”
   “Possible” is a word here warranting caution. Yes; it might do all this. But the materials physicist I consulted with thought that this deforming (or “break” as he called it) would likely be no more than about two percent, and while it would cause a more “turbulent” field to go to the cartridge, this field might actually produce more hum, or produce a hum that is slightly less but nevertheless is different and therefore more problematic. All three of the people I consulted with came to the same conclusion: Their view (which was mine from the beginning) is that with a copper insert we have metal that is closer to the cartridge, even if only by a couple of millimeters, so it therefore would seem more likely to cause problems even if this problematic effect is miniscule.
   Aside from this bit of advice by Dave, I am thoroughly puzzled by his simile: “Kinda like a fat man sitting on a pancake ... the pancake is still there, but it’s hard to get any syrup on it.” I like this image, but I have absolutely no idea what sonic application it has. Suppose we were to modify this image slightly, to wit: “Kinda like Twiggy sitting on a pancake ... you can see only part of the pancake, but when you pour syrup on it—atop Twiggy’s head so it can follow every Golden Ratio of her corpus as it slowly flows in rivulets to that pancake, then you end up with a situation where you can eat part of the pancake, and even lick the rest of the syrup up off the floor.”    There are problems with this simile too though. First, I’m still not sure what application it has to sonics. Then there is the issue of Twiggy’s modesty, given that she would have had to remove her clothes to keep them from being soiled by the syrup and also to keep from spoiling the “Golden Ratio flow” of the syrup as it makes its way to the floor. And, most alarming, there are concerns about the chastity of any males participating in this experiment which, de facto, is committing the egregious scientific sin of commencing without the luxury of an hypothesis.
   So you see, Dave, similes are often dangerous. They lead to other similes, some of them unseemly similes. And, not the least of our considerations here is the effect of causing a certain gentleman (yours truly) to comport himself in a way which almost (if not quite) compromises the stature of his virtue.
   But, to conclude with regard to a proposed weight: There is the Golden Ratio which is mathematically perfect, there are the objects of the universe which only approximate the Golden Ratio, and then there is the mystery as to whether the Golden Ratio applied to a record weight would even have any sonic benefit. This could involve making a lot of weights, doing a lot of listening, and given the price of ebony (or African blackwood, and some of the other exotic woods that have been discussed herein) a lot of gold-standard currency to pay for it all.
   But very soon I want to proceed toward leaving off with these cerebral cogitations, and get something material in the works. Hoping, all the while, that this is not a totally futile experiment. In truth, I have considerable doubts that the result is going to sound better than my existing acrylic clamp, which is the best of probably 50 weights I have tried thus far.
   Thank you again for your considerable input, and also for your patience as I have clumsily proceeded along this uncharted route.

Chronically (and never
casually) curious,

Francis Baumli


   

[KenSeger]

A few random thoughts here.  Everything with a given mass and the ability to deform can support a resonance.  And since we are speaking of an area of concern in which the deformations (movement) distances are microscopic, it doesn't take much.  The classic example of a square room with one monstrous eigentone is easy to relate to since we can hear and feel the results, plus the measurements (speed [time of travel] of sound through air and wavelength) are in terms that we are familiar with in everyday life and can visualize (pipe organ pipes).  However, when we go into a solid medium such as wood (balsa through teak) or metals (iron, copper, aluminum, brass, solder)  our sense of familiarity goes off the rails. Just because it is hard to visualize or measure, doesn't mean it's not there and affecting something.
Back to our square room, ratio of 1:1:1, calculating the fundamental resonant frequency of that room is easy, and you only have to run the main numbers once.  Then divide by 2 and multiply by 2,4, 8 for the main harmonics.  A room with ratios of 1:2:4 is only a bit more math, but should sound equally terrible.  Any resonance pattern that is not an even multiple of another frequency/distance isn't going to add additional db to an existing resonance.  The golden mean is just one ratio, 1:3:5 was a popular idea in the 1950s for speaker boxes.  The epitome of audio non-resonance would be the interior wall shape of any Vapor Audio speaker box.  And for the solid, rather than air side, the laminating of any given wood in which the wood grains are not co-linear tends to make the natural internal resonance of the wood 'fight' each other.  This is why you don't make a xylophone out of plywood or OSB (https://en.wikipedia.org/wiki/Oriented_strand_board).  The more plys the better, and again the speaker boxes from Vapor Audio win this trick in spades.
     As for metals, magnetism, and little cylinders of same inside wooden hockey pucks.  Has anybody thought to measure the impedance or resistance between the turntable spindle that touches said cylinder and the turntable ground?  Any Faraday Cage in a storm?
Ken

[daves]

Francis, I would have much preferred Jeanie Shrimpton over Twiggy. Much better reasonating  structures.

[Baumli]

Dear Dave,

But you were the one wanting access to that pancake. So I was thinking of the female's nether end.

You can't have your pancake and eat it too.

Culinarily yours,

Francis Baumli