Best TT plinth material, cost no object


It is said that the best material with which to build a loudspeaker cabinet is LEAD, the second best is concrete and the third is Aluminum. Only the third has been adapted by the industry, for obvious reasons.

Internal and extraneous vibrations need to be dampened or eliminated if sound smearing is to be reduced,

Now to the turntable; remove it from the influence of vibrations, internal vibrations not withstanding, and the vinyl should sound better.

Not all of us can put the turntable outside on the sidewalk where only the elements can affect the sound, but can we make the plinth so HEAVY that we can come close to removing the turntable from the sound room entirely?

Can a lead plinth, not too practical, get us as close as possible to putting the turntable outside, on the concrete walk?

Your thoughts, Ken
kftool
Theaudiotweak, Not sure whether I would agree with you, but check out the new TT Weights turntables if you like brass.
My choice would be brass or bronze the metals of music and the grounds for resonance transfer. Tom
Raul,

Being able to enlist the facilities and expertise of those in the scientific community is something that happens because of luck or money, maybe both.

There are a few tables that have been designed by those that have both, and more, of the above attributes. Forsell, Continuum, Grand Prix, and maybe Larry Denham at TTWeights. I'm sure I've missed a few.

However, for those of us clearly outside the league of the pros, we have access to the most cost effective brain trust in the business; Audiogon. The amount of information available on this web site is free and comes from many that have listened, fiddled, modified, evaluated and fiddled again. One has only to read the many threads and make an educated guess as to what path to follow. You gamble your bucks and report the results. If you don't lie about what you hear, it might help another member in his quest for something a little bit better. After all, don't we all think we have something to contribute that will make things sound a little bit better? If we try and it doesn't work, what can we always do, LIE!

Ken
Oilmanmojo,,

Hi to Mr Mojo.

I've been stung twice on Maplenoll tables.

A few years ago a friend of mine in the UK, who has saved me many dollars on a number of tone arms and other gear, found an Ariadine on Audiogon for $2,500. It was listed as domestic sale only, 9 / 10 condition with factory shipping crates but pick up desired. I fronted the cash and drove from Richmond to Pa. to pick it up. The arm was bent due to a baseball glove having been dropped on it and there were no crates. I lugged the table , with the 50 lb platter, back home and built a fantastic crate for it. It took a full sheet of 3/4 inch plywood, $100 of ethafoam, and a day to build it. Fed Ex got it there for $450 including duty.

The seller was an FM finatic so I took along a Wiengard 12 element yagi, one of two I bought and never used, I gave it to him gratis, that was before I saw the damaged table and no crates.

James loved the table and reciprocated, in spades, the next time I needed another tone arm.

Giving negative feedback to an Audiogon member that never had, or probably never will, sell anything again is no consolation for getting a raw deal. God will get him for that!

Ken
ken
Don't you just hate that:^) people who falsely advertise a product. There were so many different platter designs for the various maplenoll table. My first one (white ariadne reference) had a 30 lb platter that had been dropped and bunged up. I personally leveled and reformed that one to the point it worked pretty well. When I purchased my second maplenoll (ariadne signature), it came with the large platter that once again had been damaged. I took it to a machine shop and he leveled, and balanced the platter. It was approx 85/90 before leveling. the final weight is 82lb. The apollo table i recently purchased is a little lighter and designed a little different since it has a vacuum system as part of the platter.
Thorens has made the Thorens Concrete, made of... you guessed it, concrete.

I guess that pretty much cements Thorens place in history.
Hey Lewm,

There is a very nice cutaway of the Kenwood table at: http://www.thevintageknob.org/KENWOOD/L07D/L07D.html

dave
Dear Ken: This is only my thoughts on the TT subject:

you are one of the more passionate human been in audio that I know and this kind of passion is the " drive " that carry on to a person to achieve almost any target.

I don't know which is your professional career ( studies. ) and maybe the science aplication to meet TT solutions is not a job to one person because it is not only that you have the knowledge but you need a full laboratory to find those TT solutions once and for ever.

So, I think that a institution like an University could be the best place to " fix " the TT questions. It is possible to ask this kind of help/support to these kind of institutions? through a friend that has contact with?.

I don't know it is only an idea because we find here in México ( through a friend. ) this kind of help in our self design tonearm and maybe you could make the same.

regards and enjoy the music,
Raul.
Dear Intact (Dave?)
I agree with your statement about logical structure. That's why I embarked on the project of acquiring the idler-drive and direct-drive turntables and then making slate plinths for them, so I could hear for myself in my own system. (I also bought a Garrard 301, but I realized along the way that I had no energy left to wade through the Garrard options, plus I grew to love the Lenco, so I re-sold the 301 with no plinth.) Little did I know it would take the better part of two years (of my "spare time") to identify and solve the problems associated with making the plinths that I did make. That's also why I don't feel qualified to make any broad generalizations, beyond slate is "good". Something else might be even better.

I neglected to mention that the Kenwood engineers apparently also valued the idea of Constrained Layer Damping and the use of disparate materials perhaps to spread out the resonances. The L07D plinth is primarily made of the very dense cement-like material described above (if you look at a photo of the L07D, the stuff I am talking about is painted dark bronze or brown and is the major visible structural element), but hidden below and around the motor/platter area we have a sheet of thick stainless steel or aluminum. Below that is a very large piece of intricately cut hardwood (mahogany maybe) which is bolted up to the bottom of the chassis by at least a dozen metric screws that anchor into the stainless steel pan. (The wood piece can be seen peaking out around the side edges of the plinth; it is painted light gray.) Finally, that stainless steel or aluminum piece that surrounds the motor gives off a solid metal "arm" that goes all the way to the tonearm mounting platform, forming a firm coupling between the bearing and tonearm bass, which also contains a very heavy brass anchor-weight. Those guys were not fooling around. When I first acquired the table I had the notion of replacing that hardwood piece with a piece of slate, but it would take both a waterjet AND a CNC machine to re-create the shape in slate, I will leave well enough alone.

Maybe the answer to the OP's question is that it takes a real knowledge of materials science and that possibly a variety of materials used together in a certain kind of "sandwich" would make the best plinth, cost no object.
Thorens has made the Thorens Concrete, made of... you guessed it!

http://www.thorens-info.de/Concrete_sme3009.jpg

http://digilander.libero.it/bellocaddo/turntables/concrete.jpg
Always nice to hear that some mini meets are organizing. It is a very positive way to compare and learn from each others, especially in turntable plinths department. Don't forget to report your meet impressions !

Jean.
Hey Lewm

thanks for the explanation. what you hear is what matters. the reason I struck up the conversation was to get a better feel for the background of your experiences. I am 100% in the "what sounds best" is "best" camp, yet I still feel I need to adhere to some type of logical structure for collecting data based on experience.

dave
Ken, That would be great, either way. I live just across the American Legion bridge on the Maryland side of the Potomac but right along the river. I am very anxious to get my L07D up and running. Now how is this relevant to the thread? Have any of you guys ever examined an L07D plinth? I don't know what it's made of, it looks and feels like cement and it is as dead as cement but seems more dense than cement. I think it's a proprietary material that Kenwood invented for their top of the line turntable, ever. But they were thinking about the significance of the plinth material in a dd turntable more than 30 years ago.
Hi Lewm,

Howard and I are just a few minutes apart. As you may know, Howard has four L o7d tables set up and running with different cartridges that afford him the ability to match the music to the cartridge of choice. It's hard to beat a combination like that!.

I guess you and I are distant neighbors. I generally travel through MD four or five times a year. If I might, I'll email you the next time I'm in your area. If it's convenient maybe we could connect for an hour or two and compare notes. Conversely, if you ever get to Richmond please let me know as I'd enjoy a meeting. Maybe I'll even have the table done by then.

Ken
One could just as well posit that the differences in sound among the 3 tables are primarily due to unwanted resonances, either within the turntable mechanism or from the respective plinths, and that slate either dampens the chassis resonance or eliminates the resonance of the factory plinth by replacing it entirely. Once that happens, if you play the same LP on the 3 turntables, you would expect/want them to sound more (but still not exactly) alike. That's what I hear. What favors that hypothesis is that the sound is more neutral. The 3 turntables did not take on a "similar characteristic" so much as they became more neutral to my ears. I suppose you could say "neutral is a coloration". There is no resolution through discussion. That's the beauty of it and the frustration too. I am not saying that slate is the only way to go or even the best way to go. But for me, it's all good.
I realize that the experiments are not comparable but it seems to me that you used three distinctly different sounding tables into a common plinth and they all took on a similar characteristic. I guess the proper thing to do would be to try a different material for all three decks and see what happens.

If I had to choose based on the system as it was, I would have gone with the ebony / Zebrawood, but if the tests were done in my system I suspect the preference would have been something else.

dave
You put one chassis into plinths made of 4 different materials. I put 3 entirely different chassis' into plinths all made from the same material. The two experiments are not comparable. In response to your speculation about coloration, each of those three turntables has a characteristic coloration when auditioned in their respective stock plinths. In slate, they all became much more neutral sounding (which made them sound more alike but not exactly alike) AND the best qualities of those two drive systems (idler and direct) were not merely preserved but enhanced. That's all I can say.

So which plinth did you prefer? You did not say.
Hey LewM

You mentioned that putting three different tables in a plinth and they all sounded more alike. This makes me wonder if the plinth material is dominating the sonic character and not the tables themselves.

I recently heard the same 301 in the following 4 different plinths, Slate, Maple, Delignite and a three layer ebony and zebrawood sandwich. All 4 sounded quite different and declaring one of them "best" was really a matter of taste and system matching. Each one did show a different character and my ultimate preference probably had more to do with how the plinth complimented the system it was going into. These were rather quick non-scientific swaps but the overall character of each material was readily heard. In a few months we hope to repeat the swaps in a more controlled environment with the goal of putting a sound on the various materials.

dave
Dear Lewm: That's why I posted the meaning of that word in Spanish, Certainly I'm not trying to say that any one or evrybody are " deliberate liar ": if any of you take it in this way an apoligize for that because that was not my intention.

Thank's to let me know the English meaning of that word.

regards and enjoy the music,
Raul.
Dear Halcro: I use that word ( maybe wrong word ) because I read it in a post here. I don't know what means for sure in English and that's why I posted what means in Spanish: talk with out sure foundation.

The TT subject is an " old " one and everybody talk on different TT topics but I can't see true " solutions ". As I posted IMHO the TT subject can be solve through science but the fact is ( I don't know why. ) that no one consider the " science road " like a true solution or like an alternative to all those " common sense " in the last 50 years.

Henry, please change the " charlatan " word ( it is not important, only a dramatization. ) and take a look to all TT manufacturer websites, TT pro-reviews and threads/posts on this forum, what you can find are " talk " and retoric but not scientific/test/measures/proves that support true TT solutions to so many TT " subjects "/problems.

Now my questions are: why no one take the science road? what's wrong with? there is something that we can't understand about? is that so complex that preclude the use of science for an integral TT solution?

What do you think?

Regards and enjoy the music,
Raul.

Dear Ken, I take it you must reside in the Richmond, VA, area, if you live near Howard. He currently has my Kenwood L07D motor and power supply for parts upgrades and calibration. I look forward to having it back here in Bethesda, MD, for my first listen. We aren't too far apart.
Dear Raul, I think it is a bit too strong to use the word "charlatan" in this regard. In English a charlatan is a "deliberate liar". If anything, most of us are only guilty of generalizing too broadly from relatively limited direct experience or controlled experimentation, where even in the best of circumstances, the results are based on subjective judgement. So, I can only say that seating the Lenco, Denon DP80, and SP10 Mk2 in slate plinths where I have also coupled the tonearm to the solid slate (no discrete armboard) results in making these three different tables sound much more alike than they did before. And they are all much more neutral; they have lost colorations that most of us can associate with the three products. They are more neutral without being "dead" sounding; the liveliness associated with idler- and direct-drive is still very much in evidence. Ergo, IMO, in this little experiment, slate is good.
Dear Raul,
Till today IMHO and with all respect to everybody we only have or are: charlatans on the subject.
I don't believe that there IS a "best" TT plinth material.
Just as there are tonearms made of aluminium, titanium, wood, carbon-fibre and plastic all competing at the same level, indicates to me that all materials have some benefits and some disadvantages and it's really the implementation and compromises made, which determine the ultimate worth of a component such as a turntable or arm IMHO?

Just as we debate whether the virtues of DD, belt drive, rim drive or idler drive for turntables will tell us which is BEST, there will never be universal agreement.

So instead of calling all the turntable designers "charlatans"?.....let's be grateful that throughout the last 50 year history of turntable design and manufacture, they have provided us with a practical 'laboratory' of drive theory and materials application from which we can learn an immense amount if only we knew how?

Regards
Henry
Hi Ken,

I'll be interested to learn of your experiences with the Minus K device. I should expect this would approach if not represent the zenith of isolation.

Regards,
Sam
Dear Kftool: I don't know which one is your first passion: music or build the hardware to enjoy music.

It is clear to me that no one goes with your dedication ( DIY ) to build audio items with that in deep passion if does not has an in-deep passion for the music.
I applaud that passion, go a head!!!!, we came to this " world " to be actors to transcend: good.

Now, as a DIY you don't have all the answers ( the right ones ) to your TT project and that's why you are asking about.

I can't help you because I don't have the precise answer you are looking for but if you permit me the thread bring to me some thoughts on the TT subject.

This is not the first thread where exist a dialogue about TT plinth, many threads on this subject with out any single precise answer: only people talking and talking and talking with out clear, tested and precise foundation. This has a name: charlatan ( in spanish this is what is a charlatan. ), and this include me.

I know that many of us that are not professional and commercial TT designers do not have the knowledge to give the right answer not only to your question but to almost any other TT question but exist in this forum the TT Pro that I respect but that does not have the right answers either.

That answer that was posted here: +++ Go with your best judgment based on research and common sense. ++++

not only does not help but IMHO means nothing.

This is not a " common sense " solution, we need science/enginnering knowledge here. IMHO through science and the precise/right know how on how apply the science/engennering you/we can have the answers you/we are looking for.

Unfortunatelly no one of the TT Pro ( Caliburn, Monaco, Walker, Teres, VPI, Rockport, AS: just name it. ) or any one else has a scientific tested answer to your question. No one ( at least I don't read it anywhere. ) already find which TT vibrations/resonances are pick-up by the cartridge and through the tonearm to the cartridge. Which TT vibrations/resonances ( it does not matters where they come from. ) could mean: at which frequencies, at which level(spl), which kind of vibrations/resonances affect the most and how, with which build or blend materials: at the plinth, platter, arm board, footers; a high mass is the answer? where are the scientific studies/tests that can prove it?. Lead, slate, carbon fiber, magnesium, the best TT build material? where are the scientific studies/test that prove it? and I can go on an on with no answers, only " common sense "??????

As I say this is not a " common sense " subject: you/we have to apply science/enginnering research with the right scientific " tools " to have answers with foundation where there are no place to doubts and/or " questioning ".

Till today IMHO and with all respect to everybody we only have or are: charlatans on the subject.

Regards and enjoy the music,
Raul.
Oilmanmojo,

Before I had a lead platter cast I bought a Maplenoll table that was supposed to have a 35 lb platter. I bought it on Audiogon for $750 and thought I got a deal.
When I got it the platter weighed 8 lbs. It's all still in the box; one of these days I'll sell it.

Ken
Lewm,

That is one of the many questions my wife continues to ask me.

Since I began the project I've gone through a few changes that have ALL pushed off the date of completion. The last was a year ago when I decided to add a 50 lb lead disc to the platter. I located a foundry to cast it, a tool and die shop to machine it and then months to have Sota machine a longer vacuum spindle and then put it all together. The new platter is staring at me right now.

Between Albert and a good friend in our local audio group, who hosts the Kenwood L 07D website, I thought I'd look into a direct drive table. A year or so ago I found a Denon DN 308 on Audiogon and bought it. This table is beautiful, except for the mdf plinth which will have to bite the dust, and had I bought it before I started the monster I would've saved $$$.

I have no misgivings about finishing the table I began 3 years ago but the urgency has diminished, SLIGHTLY!

The bottom line is that it's fun to build things. Once the project is finished you need to find something else to build or just enjoy the project you just finished; how easy is that to do?

Ken
Buconerro,

Your comment regarding using a base designed for electron microscopes might seem out in left field but the thought also crossed my mind. A year or so ago I looked into devices designed by Minus K. It's their business to isolate electron microscopes and other sensitive devices from vibration. The theory behind their design was convincing enough that I asked them to build one for my table. It was built to isolate a 750 lb load from lateral and vertical vibrations lower than those I should encounter. When the beast is assembled I'll see how well it works.

Ken
Oilmanmojo,

Didn't know that regarding Maplenoll tables...thanks for the info!

Best,
Sam
Maplenoll top end tables were built with a platter of pure lead (ariadne 80lb platter, apollo 70lb platter), a plinth that had a lot of lead and corian. Walker audio is built along similar lines concerning the platter and plinth. These tables are not easy to set up, move or tweak as a result, but once properly set up, they do provide a very "black" background. With other tables, i found i could "tap" on the plinth and hear it out the speaker. Not so with the maplenoll, even the ligher weight ariadne reference that i initially brought. FYI, the maplenoll Ariadne signature weighs about 175 lb. The Apollo i have, about 210.
So, Ken, why isn't that project finished and what might you not like about the behemoth you built? Maybe that could lead you in a good direction. None of us have your skills in the first place. Many latter day belt-drive tables have virtually done away with a formal plinth and sound great. It seems based on word of mouth that idler- and direct-drive turntables do benefit greatly from a heavy, dense plinth intimately coupled to the motor/bearing. (But there are guys who like the Technics SP10 sans any formal plinth.) My own experiences with slate are in agreement with the idea that slate is very very good. (I have now made or had made slate plinths for Lenco, Denon DP80, and Technics SP10 Mk2.) But I would never claim slate is categorically "the best". Moreover, there are several different kinds and densities of slate, even within the US. For example, Vermont slate seems denser than Pennsylvania slate. I have no idea what that might mean. My SP10 plinth is made from Vermont slate.
Odd that so many people fail to consider the significant vibrational energy that is being created by the stylus, enough energy that you can hear it. An electron microscope base may just make sure that the energy has no where to go. Acoustic energy from being in the same room is often trivial in comparison.

A good plinth needs to either dissipate internally generated energy or transmit it into something that can. Otherwise only part of the problem is solved.
Thanks Albert, alias " Alley Cat," as I forgot about the posting . It's been three years since I began the table and it's still not done.

Ken
Buconero117,

Should the electron microscope base be accompanied by a scanning electron microscope - brilliant images of styli can be had! :-)

Best,
Sam
Buconero117
I read that so often to move your TT to another room. My problem with that is, once the tonearm sets down in the groove how much time does one have to run back and sit down and get into position?
When I move my turntables from wood, metal or acrylic plinths to a slate plinth they all sound much better. Invariably. I still have not found a better plinth material yet.

Jean.
Next to the sidewalk, best it go into an adjacent room. One of the neglected issues related to TT's is the acoustic energy the is flying around the listening room. It always is impacting the arm and cartridge, no matter what the plinth material is. Once you have it in another room, best to put it on a cost no object base. What is that? About $30K for an electron microscope base, then serious listening can begin.
Yours is an interesting question, and if you find someone who gives you a definitive answer, you have found one of the many charlatans in high-end audio. If you find anyone who seems to know too much about this hobby, you have found a liar.

That said, I use slate in my turntable, and it is great. Why? It is simply because I designed the rest of the components to work with it. Then again, I have attended shows where I heard various turntables, some without plinths as we know them, that had an absolutely stellar sound. Still, there are materials to be used with care. Lead is one, mdf is another.

I'm reminded of what an industry insider told me when I first started the journey of making turntables, "No one really knows about audio, regardless of his stature or experience." It is an unending quest for a nirvana that may not exist.

Go with your best judgment based on research and common sense. It's the best you can hope for.

.
there is no real one answer to that question. I would say that if you place most TT designers in one room they would all most likely have their favorites and prejudices.