A Copernican View of the Turntable System


Once again this site rejects my long posting so I need to post it via this link to my 'Systems' page
HERE
128x128halcro
Dear Thuchan, Not sure I understand just what it is that I might disagree about. I don't feel very contrary about anything except maybe outboard tonearms.

As far as mounting two (or more) arms, it's just a matter of allocating enough space surrounding the actual chassis on the surface of the (slate, in this case) plinth. I designed mine with a lot of flat surface area and no traditional "hole" over which to place a tonearm mounting board, so I am restricted to using surface mount tonearms. (Tonearms that do not have a vertical shaft that needs to reside below the level of an armboard, e.g., Triplanar, Reed, Grandezza[?], Dynavector DV505, RS Labs RS-A1.) So the tonearms are mated firmly to the entire mass of the slate with bolts that go all the way thru the thickness of the slate, which I think is a very good thing for sound quality. If I were to start over, and I may in fact do so, I would re-design my slate plinths along the lines of Steve Dobbins' plinths and also the Saskia. If you look at those, the discrete tonearm board is held firmly to the main plinth by a single large bolt, so it is well anchored but can rotate in space outside the confines of the plinth surface entirely and therefore has a wide range of adjustment to accommodate various sizes and lengths of tonearm. The Dobbins plinth for his new direct-drive turntable, The Beat, is very well thought out for two tonearms. Beautiful and beautiful sounding, in fact. (Heard it at RMAF.)
Dear Lewm - maybe got it wrong!
thanks for your explanations. Agree that slate is a wonderful material. I heard the Beat at RMAF too and I do share your assessment - this was one of the highlights, really good sounding
Pity we did not know enough to find each other at RMAF. Next year all of us need to do a better job of making plans in advance of the event. I went to the Mexican restaurant for the vinylphile meeting on Friday but could not identify anyone to talk to except Win Tinnon, with whom I had made prior arrangements.

Funny that altho I have strongly rejected the idea of an outboard tonearm pod, I have involuntarily been dreaming up a way to make a really heavy one using a cylinder made of bronze that can be purchased direct from a metals company here in the US, in a wide range of diameters and almost any reasonable height. The mind cannot rest.
Dear Lewn - you wrote

"I have involuntarily been dreaming up a way to make a really heavy one using a cylinder made of bronze that can be purchased direct from a metals company here in the US, in a wide range of diameters and almost any reasonable height. The mind cannot rest".

www.metalsupermarkets.com

And reasonable cost too. They make it real easy for you by cutting on the spot.

I have a picture of one of their shelves in my gallery link that I posted earlier. Here it is again.

http://www.canuckaudiomart.com/view_userimages.php?user_id=5181&image_id=39023

Lewn - I bet you will continue to be tormented by these visions until you try it out - :).

As an update I have been contacted privately by two individuals who are trying this out. Plinthless and separate armpod. I have encouraged them to post but they choose not to - at least not here. One of them uses a panzer plinth with his SP10 and also has a Raven.

Looking forward to hearing from them during the winter and I hope they decide to post their impressions here if they read this.

Cheers Chris

Well it would be most interesting to hear from Mr. Panzer plinth. I assume its made of hard wood, not from a 20-ton armored tank.

Did I actually write "bronze"? I meant "brass". I have already bought some brass pieces from that company, in order to make subweights to go below the bases of tonearms, and to make an energy sink to go in the plinth for my SP10 Mk3, with a threaded brass bolt pushing up gently on the bearing housing, a la Albert Porter. They also sold me the treaded brass rod from which I and my friend made the needed bolt.
Halcro,

I just came across this thread and thought I'd chip in my penny's worth. I've recently been testing my Technics SP10 Mk2 with and without plinth. I would definitely say that "without" plinth is the way to go. The music almost seems to be released with the loss of the plinth and staging and timbre are enhanced in a way that just sounds more natural/real (almost like, 'free your TT/ free the music'). Better still, you improve the sound while saving money: that can't be bad.

I simply sat it on some Audio Technica AT616 precision pneumatic footers and attached an ash armboard. I would strongly recommend you give it a try. I was a sceptic but hearing is believing.

.
Halcro,

Sorry, I was responding to your relevant posting on your Systems page and now see that you are already trying this and that we agree. I suppose the removal of any potential vibration and the minimalist approach to analogue might seem obvious.

Congrats
Dear Dgob: Nice to see that you too take that " flag " and that like it.

The critical point here IMHO is that you decided to test it and the good thing to you is that the rewards you received on change was way worth to made it with almost no $$$/effort.

Well these kind of facts is IMHO a good forward step to improve quality permormance level on those TT and many others.

One more time where " less is more ".

Btw, all of you owners with the plinthed alternative could try ( with out almost no effort or serious modifications in your analog rig other than a change in VTA/SRA/Azymuth. ) my advise to Lewm for use three small tiptoes ( metal or delrin. ) atop the TT plinth and the TT ( it self through the outer metal chassis/frame. ) over those three tiptoes where now that plinth mainly will function as an arm board.

Please try it, you don't lose nothing!! and the experience could give you more than only " fun ".

Regards and enjoy the music,
Raul.
Dgob, I went to your "system" to take a look at the photo of the AT feet. I see you have 3 different kinds of AT feet. Which are you using under your SP10? I am guessing it is the largest set, at the rear of the photo. Those smallest AT feet in the foreground - I used to have a set myself. I have no idea where those disappeared to, or when they disappeared.

Off-topic: How do you wire up your DD12s with respect to the Talon Hawks? Do you use a hi-pass filter on the amp that drives the Hawks? Thx.
Dgob,
Welcome to the 'Nude' club.
You at least did the comparison.
It would be helpful for others here if you could perhaps describe the plinth that you 'abandoned'?

Cheers
Henry
I use the AT 605 feet (the smallest ones amongst the 3 in dgob's pic) on my sp10. I didn't even know there were larger ones. The small feet work fine and the large ones are probably better suited for using under heavy plinths. Someone posted that the 616 (the largest ones) are rated to hold 15kg EACH.

I going to get some of those larger ones nevertheless, just to see if there's an improvement.
Dear Banquo363: Yes, 15kg a piece. These AT footers are way different to the 605, the 616 are pneumatic design that take away vibrations/resonances from the audio item and impede too that come in any vibrations/resonances coming from where the AT616 are seated.

Something that the 605 could do it but at lesser quality performance level and yes there will be a huge improvement when you test it.
The 616 is out of production and not easy to find out and I can tell you that one 616 footer is more expensive than the 605 set.

If you can find is worth the effort, I own three sets and like Dgob I'm satisfied with.

Regards and enjoy the music,
Raul.
Thanks, Raul.

Ok, I get first dibs on the next set of 616 that go up for sale.

Seriously though: what is the function of the weight guidelines for footers? The sp10 mkii weighs around 20 lbs, so one of the 616 would be sufficient, weight-wise. That would make me infer that 3 or 4 of them would be overkill and, more to the point, counterproductive. But if Raul's' right, then that inference is bad.

Perhaps the weight guidelines set an upper limit but not a lower one? No matter, I'm getting a set as soon as some become available.
Dear Banquo363: The AT616 operate from audio items in the 10kgs to 60 kgs weight range.

These insulator are beautiful made with a very high quality and where the 605 looks like a " poor toy " but the more important subject is that its three way insulators works really fine.

I used not only with my TTs and TT motors but with my subwoofers too and works very good on both items.

Regards and enjoy the music,
Raul.
Lewm,

Yes, the largest set are the AT616 footers. The others work well also, I think.

Worth a try if you see any going (Yahoo Japan often has variations).
Hi Lewm,

Raul and Jose sorted my set up with the crossover filter for the Talons built into the Levinson amp (Raul could give you more information on this) and the subs using their own filters. They all run from the pre outputs on the Essential 3160. I use the subs like mono's: left output driving the left sub and right output driving the right sub.
Halcro,

Glad to be aboard. I'm now trying the stand alone armboard. Well, actually I've just removed the armboard and fixing column from my Acoustic Signature Mambo and ficed that in place. Looking forward to trying that out.

Cheers
Y'all realize that by going 'nude', that the platform has become your plinth, right? The same rules apply.

Now if the original plinth has problems, is not acoustically 'dead', IOW has a resonant signature, it may well sound better to switch things up.

I think you will find that the mounting for the platter and the tower for the arm will sound their best when coupled as tightly to the non-resonant platform upon which the resulting turntable is being constructed.
Dear Banquo et al, Of course there will be an "improvement" when you go to the bigger feet. This stuff has become so subjective and so uncontrolled (in the scientific sense) that there is a huge placebo effect. If you are prepared to like it, and if your turntable does not actually fall to the ground, then you will like it. This is in no way meant as an insult to you personally. It's just a part of this crazy hobby.

Conversely, by the very fact that I am not prepared to like it, I probably would not like it. It cuts both ways. Now I will retreat to my bomb-proof shelter.
I agree totally with Atmasphere - there is always a "plinth" ( in the sense of a common ground for bearing and armpod/armbase/armboard ), even if it is not always apparent as such ...;-) .... so, - sorry to burst some bubbles here - it is never really "nude" .....
After all it is still audio....
Cheers,
D.
Dear Lewm: So, that's means that all you own in your system were a placebo like where things are you were ready/prepare to like it? or it is only the " humor " you wake up today?

Regards and enjoy the music,
Raul.
Dear Atmasphere: Yes, that could be a " plinth " but that is not the subject here but the TT naked it self .

In this same thread I posted that we always can hang on the TT from the ceiling and now what : the ceiling is the " plinth ".?
The subject is way different.

Regards and enjoy the music,
Raul.
Rauliruegas, OK let's go with that for a moment. You hang it from the ceiling- where is the tonearm? Hanging also? On a separate string? Obviously *that* is not going to work...

So, you have to connect them together somehow so the sacred geometry is maintained. And that is just so tracking errors are minimized. So how are you going to do that?? A platform? Now the signature of the platform is the signature of the system. You could use some sort of bar or strut to hold things, again, any signature in them will be heard.

So the model does not seem to hold up.
Of course there will be an "improvement" when you go to the bigger feet. This stuff has become so subjective and so uncontrolled (in the scientific sense) that there is a huge placebo effect. If you are prepared to like it, and if your turntable does not actually fall to the ground, then you will like it. This is in no way meant as an insult to you personally. It's just a part of this crazy hobby.

I see your larger point, Lewm, but really I'm not prepared or fixin' to like any particular kind of configuration. True, I expect the larger feet to make some difference--why shouldn't I since I'll probably end up paying a chunk of change for them?--but whether I prefer that change or not is up for grabs. After all, they'll be easy to sell. Placebo probably would play a larger role if one couldn't sell after trying.

I take a very practical approach to this plinth(less) issue. My table didn't come with an attached plinth, and since I found it to sound pretty darn good without it, I'm sticking with it for the time being and trying out closely related configurations. I can honestly say that if I had some plinth ready to hand, I would immediately try it out to see what difference it makes. I take it that Chris's and Raul's point is to suggest the converse: if you have a plinth, take it off and see what happens--you may be surprised.

In my opinion, that minimal kind of experimentation won't settle the larger debate, but it might transform one's picture of the debate. However, I agree with Dertonarm that even if we had many hands going up saying that their experiment led them to believe plinthless is better, it would still leave a rather large hole in our understanding of why that is (if it is at all). There should be some 'reflective equilibrium', as the philosophers say, between observed findings and theoretical explanation. Pure theory and a rhetorical reference to 'physics' and what it allegedly tells us is pointless when it flies in the face of repeated observation; conversely, 'mere' observation is empty because it just gives us data points without a theory to tie them together.

At any rate, Yahoo Japan is not easy to navigate. Are there any other options to find these feet? I've been perusing Hi-Fi Do Japan. Very cool site--but alas no feet as of yesterday.

that the platform has become your plinth
Well OK...... then turntables with plinths which sit on bases have two plinths?
:-)
Let us agree that at least we 'Nuders' are eliminating one plinth?

And does that mean our amps on shelves or stands also have 'plinths'?
And our tuners, CD players etc?
How about our 'plinthed' speakers?.....because they sit on the floor or stands?

I think you have to understand the lengths that most of us go to, to de-couple and isolate our speakers and turntables (and many also their amps), from this shelf/stand/floor/plinth.
If you look at the transmission of various frequencies through the tiny contact points of 'spikes' or through various decoupling materials used as isolating bases, it becomes apparent that this differs enormously from that of the contact made by the turntable in its traditional plinth.

I have heard that Ralph's famous amplifiers do in fact sound better when mounted in a Panzerholtz plinth :-)
I think you will find that the mounting for the platter and the tower for the arm will sound their best when coupled as tightly to the non-resonant platform upon which the resulting turntable is being constructed.
Pure supposition and theory with no proof or evidence offered?
This is not worthy of you Ralph.

We 'Nuders' and 'Armboard Isolators' are reporting our practical experiences.
It is slightly galling to be told that 'theoretically', in someone's unproven opinion our experiences are invalid?
Dear Halcro: You are IMHO spot-on in your last two posts.

On the first " plinths "+ subject we need to think " too " that not only the floor works as a plinth but the Earth's nucleus too!!!!

In the other side a debate exist only because the ones that are argue and argue and argue does not try yet the whole " naked project ".
At least we advocates to the naked project have targets like: improve the quality performance and through that project we taked a step forward in that direction and we all are enjoying the music better than ever through that project when the people that are argue are enjoying almost nothing because IMHO no one can enjoy that kind of " words/bla bla ".

So what they have on hand?, almost nothing to argue but theory that can't prove through real experiences.

In the other side day by day are growing up the people number that are testing the naked project and till today everyone of them are satisfied with this alternative against the other one.

Welcome Banquo363!.

Regards and enjoy the music,
Raul.
Dear Dgob – Looking forward to your impressions of how the sound changes when you isolate the armboard. I did not see any value myself in attaching an armboard to a surface containing a motor and vibrations so I went directly to an isolated armboard. If the improvement that you noted was based on this alone - I can’t imagine how much better? your next step will bring. It also speaks volumes to the top end component that an sp10 is.
I really believe the SP10 engineers didn’t realize how good they made it. Think about it – they didn’t know what type of structure alias plinth - the broadcast studios were going to put them in - so they made them “bullet proof” to work great without a plinth anywhere. They had to - they wouldn’t have become the standard worldwide if this was not the case. Conventional wisdom said put it in a plinth so they made plinths for it as well to sell. This is the same reason I started with a plinth - go with the flow. It took a lot of courage Raul to keep up the front on your side. Henry it was your thread with the pictures that got me going. Kudos to both of you. I am listening tonight and I can’t believe the sound.

I have a seasonal summer cottage in the woods. This whole thing is starting to remind me of catching mice except in a good way here. For every mouse that you catch there are ten-fold and more lurking somewhere else in the structure. As we speak there are probably “x00’s” maybe "x000's" of folks trying this out as Raul has referenced. If the thought of this is forcing some folks to cringe and hide or talks words around it so be it. My SP10 and ET arm hasn’t fallen over yet. Hearing is believing as Dgob said. Something tells me they are all trying or planning on trying it too really soon - they just are not saying anything ………yet :) This is just too big a deal for us turntable people to ignore or talk words to.

Cheers Chris
Dear Banquo - I forgot to ask in my last post how you are making out with the repairs on your sp10 ?

Also - maybe one of the members here can hook u up with a plinth to try to compare with your current setup ?

Dear Chris,
Thanks for the kind words and yes....kudos to Raul for planting the idea for the 'Nude Turntable' in my head.

You may be right about lots of other people now trying out the same experiment as my Thread is recording an average of 100 hits every day despite the fact that it doesn't appear on this site and they have to go searching for it??!!

Hopefully some of these 'experimenters' will eventually contribute their thoughts in this Forum?

Knowledge is free.
Halcro,
Regarding your last post of 1/27, I think the 'theoretical proof' that Ralph offered earlier in the thread more than covers the issue regarding the desirability of having the tonearm mount absolutely stable in space vis-a-vis the turntable platter axis/level. Any movement between the two will show up as distortion. There is no getting around that.

If I were going to decide to 'go nude' with an outboard tonearm pod... I would...
1) build a tonearm pod (or three) like yours - I think it is a great design - VERY heavy with threaded bottom allowing one to spike it to a platform,
2) mount the nude TT to the same platform that the tonearm pod was mounted to, probably using the same spikes as on the tonearm pod,
3) I would put pneumatic footers, if any, between the 'platform' and whatever it was mounted on.

Banquo,
As regards putting 'light' objects on pneumatic footers with very large weight limits... I think the value of using pneumatic footers is to reduce the resonance frequency of the mounting to as low as one can in both the horizontal and the vertical. If one mounts a 10kg object onto 3 footers which can EACH carry 10-20kg, I expect that would be a problem. I have found when I have used platforms and pneumatic/magnetic isolators that it is always better to be at the heavy end of the range rather than the light end.
T_bone is absolutely right - any damping (pneumatic, oil-based, elastomer - whatever) will only reach its optimum read: lowest possible) resonance frequency and spec behavior at its maximum load.
So here for once any over-compensation regarding parts is not just futile but entirely contra-productive.
That's why even most high-priced isolation platforms do need additional load in addition to audio components resting on them to really "work" the way the are designed for.
Same regarding the other points in T_bone's post. They are correct and describe the correct way to handle the topic if going for a TT without "classical plinth".
Cheers,
D.
post scriptum: I wonder why this thread has to be searched for and isn't available anymore through the Analog Forum's front page ... any idea anybody ?
Dear Dertonarm,
Thread is visible on my front page but Raul also couldn't see it?
Don't know what's going on?
Dear Halcro, yes - it is on your front page, but not on the "Audiogon forum analog"-page.
Means that one indeed has to search for your thread - it can't be find among the current other threads in analog.
Very strange indeed.
T_bone,
What you are saying and what Ralph is saying seem to me diametrically opposed?
You and I are in total agreement, in fact the postulation of this thread is that the armpod is fixed and the geometrical relationship to the platter is correct and stable.
What Ralph says is
mounting for the platter and the tower for the arm will sound their best when coupled as tightly to the non-resonant platform upon which the resulting turntable is being constructed.
Coupled TIGHTLY to the platform!!

Here I am simply going to be obstinate.
I disagree completely. There is nothing TIGHT about the spikes under my armpods and there is nothing TIGHT about the TipToes under my turntable.
The armpods and turntable are DECOUPLED from their base (the shelf) and unless I'm not comprehending properly......you agree with my methods?
Bear in mind that the RELATIONSHIPS must be completely accurate and stable.

So DECOUPLED are all these items from each other, I can physically take each armpod away and if I so desire, I may even tuck my Nude Turntable under my arm as I happily walk my pet snake?
Dear Halcro, T_bone and Atmasphere only seem to postulate opposite positions. Whether you actually mount with screws or with spikes and high weight can result in the very same.
So your spikes are actually VERY tight a coupling to the platform (even if you can move the armpods if you wish...). The coupling force is the weight of the armpod (hopefully pretty high) divided by the touching area of your spike (very small ... ) - so the resulting coupling force is pretty high.
However with the kind of weight we are talking generally in audio components, spikes are less tightly an mounting option than a good solid screw. After all it is about coupling two masses together without possible movement of one in relation towards the other.
Armpod(s) and bearing/turntable can hardly be DECOUPLED from each other in the sense that would allow relative movement of one towards the other (which would be the very sense of "decoupling"). One can incorporate kinds of resonance-barriers between them, but they will always (or better: should...) be coupled towards each other.
This can be via a shelf, plinth, skeleton - whatever.
I think T_bone, Atmasphere, (me too ...) are talking about the very same thing in slightly different word.
Cheers,
D.
Halcro,
I think Ralph would say we are all three in agreement. To me, a 20kg armpod spiked to the same platform that the TT is spiked to means they are strongly 'coupled', even if you can take them away and walk them with your two pet snakes, separately.
"post scriptum: I wonder why this thread has to be searched for and isn't available anymore through the Analog Forum's front page ... any idea anybody ?"

Hope it doesn't have to do something with "my finding the mice" talk in my last post :) Has anyone figured this out yet?

T Bone/Dertonarm – thank you - excellent advice on the weight considerations for these footers. I hope that the talk on here about those footers doesn’t cause their market price to skyrocket now. If it does we know who to blame.
Dear Chris, I should be picking my sp10 up tomorrow. It took awhile because I kept adding stuff for Mirko to do. I'll have a tonearm pod a la Halcro which will sit on these cool feet he originally designed to replace those on the Microseiki Rx-8000 motor unit. And evidently the speed was fast at 78rpm so I told him to replace all the capacitors--I hope that fixes it, even though I don't have any 78's. The noise I was hearing was the thrust bearing, whatever that is, and he replaced it. If everything goes well, I should have a pretty good set up.

Dear T_bone and Dertonarm: thanks for your notes regarding the footers. That's what I would have thought, even though I didn't know the theory behind it. But Raul asserts the AT 616 sound great beneath his 'light' sp10. Here again we have a tension between theory and observation. No matter to me: I'm still buying them just to see, that is, if they ever come up for sale. In the meanwhile, I was looking at Edensound's terrastone footers. Has anyone tried them? One can go broke trying out all these different footers; might as well buy a plinth--ha!

This thread doesn't show up on my front analog forums page either. Annoying.
T_bone,

I have been trying my stand alone armbase for the past three days and it has not moved, despite my having been deliberately more robust in handling than I would normally. Unlike Halcro, my armbase (as can be seen on my System page) is only held in place with a few blobs of blue tac. I did take some time in adjusting to ensure that arm and cartridge were perfectly aligned with the detached nude TT but after that I have treated the entire exercise as if it was a normally fixed arrangement. As you know, I'm using the AT616 pneumatic footers and so that might be encouraging if the results althmore surprising for that.

It is too early to be certain of all my findings but I would honestly (and VERY unexpectedly) say that you should just give it a go. The differences are blatant, to me.
Dear Chris /all: The " naked TT project " is similar as what happen with the MM/MI alternative: many people are trying/testing with no posts in the threads.

Both alternatives are so un-expensive and so easy to achieve that IMHO it is an audio " waste/lose " not to try it, at least just to " cover up a hole in our audio culture ".

Btw, Banquo363: from the AT operation manual the AT616 works between 10-60kgs. It works for me and for Dgob too.

Now, each 616 footer is a set of three internal and independent insulators design where the third one works when the item weight is over 30kg.

Regards and enjoy the music,
Raul.
Whilst the thread is not on the front page of the Analogue Forum, if you go to the Recent Discourse Forums and press 12 hour, 24 hour or 48 hour link, you will find it there.

I like going this way as a routine b cause you get to see all the current discourse and in their order of popular activity.

However I have asked Audiogon the reason for this?
We're baaack.....

I re-assured the moderators that I really didn't take my pet snake for a regular walk..........it's just a special treat.
Halcro, points are a sort of mechanical one-way diode. That is they are fairly efficient at transmitting vibration in only one direction. So if your points are pointed *down* under your tone arm: welcome to your plinth, the anti-vibration platform.

Any good anti-vibration platform will have both 'acoustically dead' and 'absolutely rigid' as a mantra.

I agree that a bad plinth is likely worse than none. I've been down this path before- my turntable has been in development since the early 1990s. So the comments I've been making are based out of experience, not conjecture.

If you want to separate something, and if the 'table is not a direct-drive, then the motor might be a better candidate. However IME the vibration of the motor will be of no significance if the plinth works right.
Greetings Ralph,
my turntable has been in development since the early 1990s.
That sound exciting? I was wondering why no turntable designers were contributing to this thread?
Any clues as to which 'drive' model you're pursuing?
Atmasphere,

Just a quick question but for those of us using pneumatic footers, wouldn't that mean that the seperation of tonearm (including mount/armboard) from the nude TT represents the decoupling of both and the removal of a common plinth?

Kant demonstrated that the argument - "that might be true in theory but it is not in practise" - invariably pointed to the deficiency in a relevant theory. Maybe, if the common experience proves sufficient, we will find the reason why. That seems to be the way of progress!

Please accept my question as a genuine search for an explanation for what appears to be happening and all the best with your TT launch.

Halcro,

I have been playing with the detached armboard and note major differences in my analogue performance. Beyond question are improvements in staging and a more refined sound across the piece (I have been playing my TT at clearly increased gain levels, which I take as one sign of this). Bass is also far tighter and more detailed.

My Mambo armboard has three M6 screw holes in the bottom by which it is screwed onto the TT by an attaching rod (apparent as the armboards base in my System photograph). If I remove that attaching rod it will therefore be possible for me to use three spikes instead of the blue tac. I intend to try this out both because the blue tac approach has provided such marked differences and to see if this puts the debate beyond question.