Stitch,

the only thing that you are missing is paying attention to the OMA advertisements and truing to recognize behind it any rational beside a pimp yearling own merchandise (in fact it is not his merchandises). I told many times before that brain, ears, knowledge and listening awareness behind that Pennsylvania dirt is sub-acceptable and I would like do not be induced to comment on it again and again. Ironically, there is a manufacture in your country who dealt with the OMA dirt before and who after read my site sent me email with surprise how much I know the OMA under-hood.  He even proposed to upload in the site some of his anecdotes about OMA that in his view would make everyone se that his Pennsylvania dirt is not “nothing” but something that deserve to be squashed and destroyed. I refuse as I do not feel that truth about OMA need any “evidence”.  So, please let keep the OMA out of scope of any further attention. The only thing that would make me happy if a lighting strike the dirt, kill him, burn his house with all crap the he is trying to sell and preferably any single person who deal with him. Is it too much to ask? Jonathan Weiss of Oswaldsmill Audio is an audio equivalent of neo-cons in US politics – he uses the identical methods of capitalizing on fears and stimulation of parochial thinking.

About the Idler Drive turntables. Yes, you never see any serious thinking about it. In the best cases you see the people swear own devotion to idler TT but in all cases I was able to recognize a flows in logic and their desire to advance this or that method of transforms momentum from motor to platter. Can we presume that if DD, Idler or belt TT – all of them made with identical respect to own topology then will produce identically result?  I presume that it might be so, but I am not certain.

I have seen a few years back an article in Russian magazine where the author was trying to prove that Idler roll is the most preferable transmission as it forms a mechanical filter of lower order. Here is the link (in Russian):

http://www.shabad.ru/aml/About%20rollers%20and%20springs.htm

Saying it, I have to note that the author of the article is well knows falsifier who have a reputation to write fraudulent articles and to conceive counterfeit to ideas into public to fulfill specific marketing campaigns. Still, the conclusions in the articles are not wrong – an Idler roll does have some transfer advantages … but for very light platters. With increase of the platter’s mass I think any theoretical advantages get equalized or completely reversed. Where is the truth? It is hard to say. It is VERY difficult methodologically honest to compare TT.  There is so many valuables involved!

The Idler Drive looks like coming back. So, a few years back it was the microprocessor controlled DD. Before it was a belt or a combination of belts…. I think it is a purely marketing circus invented by idiots of Framer- Weiss level. When SME made 3012 then if few years the pips sold very expensive bronze bearings on this arm. There were a number of highly scientific and serious articles about advantage of bronze over steel. Then the same was reversed to plastic bearings. Then it went to second round and the advantage of steel was rehabilitated. Over the years each 5-6 years the fashion on the preferable 3012 bearing was rotating…  I think the same is with Idler drives. A few companies would like to make them and they make the “market makers” to spread new set of “believes”. A dozen of so on-line cronies join the chorus and the “new” revolutionary topology is born. Isn’t it how the industry proper itself? Have you read TAS blog and alike?

What is important to understand however is that revoltingly-unserious level of industry treating the different technological aspect (Idler Drive for instance) is not necessary an indication that the given technological aspect is wrong. We just do not have any answers as the audio industry never care to ask any complex or deep questions.

Romy the Cat wrote:

Still, the conclusions in the articles are not wrong – an Idler roll does have some transfer advantages … but for very light platters. With increase of the platter’s mass I think any theoretical advantages get equalized or completely reversed.

N-set wrote:

Romy, would you elaborate on that more? Looking at his formulas it looks like higher mass gives lower resonance point, which is I guess desireable?

Yes, the resonance point go lover but also the ratio of contribution”from platter” vs. “from motor” get changed with increase the platter. If to embrace the filter analogy of the author above then the idler is closer to first order filer and belt is to a second order filter. The second filter has a cap and coil and spins phase much more than a fist order filter. However, if we begin to beef up coil (platter) for instance then we can have a second order filter to operate within Bessel Q and the phase shift will be identical to first order filter.

In more practical terms – with substantial (very substantial) increase of mass makes the system is only platter scenic and the platter’s moment of inertia get dominated. Will, the idler be benefited with increase of platter mass? I do not know. Have you seen any heavy TT with idler? I do not. My presumption is that with increase of platter mass, let say arbitrary that it will happens at 30-50 pounds, the difference between belt and idler does not exist anymore. Or let me to put in this way: the sonic consequences of suspending of the 50 pounds overtake any minute advantages or disadvantages that idler or belt drive will have.

I do feel that substantially heavy platter will make a user do not care how momentum went to this platter. Take a 100 pounds platter (like American Sound TT) and I doubt that you will distinct what kind drive it had.

I have owned and played with a couple of "classic" idler-driven TTs, but I was very young at the time, and incapable of pushing the design then, even if I'd wanted to.  As it happened, I abandoned the idler TTs for a belt-driven Rek-O-Kut "broadcast" model (!), for reasons of sonics.  Even though the stock Rek-O-Kut was no better in some areas (sonic break-through and "microphonic" self-noise), it was audibly better in terms of speed control (pitch, rhythm and dynamics).

With the almost hysterical "revival" of interest in the idler-driven designs, perhaps someone has finally figured out how to eliminate the sense that the music is being "dictated" by the motor.  I would not post this at AA (for the same reasons I would not kick a hornets' nest...), but I also got to this point with my Technics DDs, and I see the problem as not only related sonically, but similarly sourced, namely too great a reliance on the motor, itself.

We've beaten this one up pretty good in the past, but I have never gotten a satisfying response to the question, how does one physically isolate the (idler) motor, itself, from the platter, since the heavier the platter, the more powerful and "connected" the idler has to be, because of its operating principle?  I can see (and hear...) how a +/- pliable belt from a "barely big-enough" motor can provide "enough" drive to a massive platter to average out nicely, once the platter is up to speed.  But I still do not understand how the "Big Motor" approach makes things better than worse in the end, based on my own experience.

Paul S

guy sergeant wrote:

Romy, besides via the radio, did you ever have the opportunity to hear either the 948 or 950 in a domestic installation?

N-set wrote:

EMT930 starts from zero in 1s, EMT950 in 0.2s...

It is interesting that any conversation about a specific technology in TT instantly get converted into conversation about brands.  We were talking about idler roles and then we get embraced into thinking of Garrard vs. EMT. Perhaps it needs to be this way even though we all understand that quality of sound (positive or negative) from Garrard, Thorens, EMT, Lenco or from whoever is NOT only the result of idler drive.

I personally have no problems with idler drive if it make properly. What does it mean properly? It means that idler connection does not exhibit any negative impact to the performance of entire TT. I would not argue what is better: idler, belt, different versions of DD or some idiotically-exotic drive methods (like magnetic or jet). The whole point is that if a given drive was made good-enough in respect to own topology then the comparative predominance of individual drives shall be absolutely identical.

I think the only subject that might be under desiccation is not which drive is better but in what TT the given drive is implemented to its optimum best. I think in term of idler drive the EMT tables went further than anybody else. But again, it was not best idler drives but it was best environment for idler drives. The EMT 927 has a huge 16” platter and idler roll is grabbing in the middle. Only the gyroscopic effect of the platter shall make this configuration way beyond what flimsy Garrards or Thorens would do.

Would it mean that EMT tables have some kind of ultimate idler drives? Absolutely not. In fact there is no such a thing as ultimate solution for TT as all TT are made to fit very narrow and very specific requirements.  In the past EMT were made for very limited and irrelevant today need of broadcast industry. Stitch is right – they did not even dream to get of TT the sound that we are trying to push out of it today. If the EMT tables perform today good then it is an accident – nothing more or less. It is like Germans, Italians of Brits made some tube in end of 30s and they have the objective that today would make us to laugh.  How the hell they know that in 70 years their tubes will be considered as some kind of reference in the sonic condition that did not even exist at that time?

I disagree with Stitch view that science today has anything to do with sound of TT. The problem is that we do not have in today’s world serious sciences who work on design and assessment of turntables.  Sure, we have a number of talented people who with best objective come to audio and try to use what they have to make an interesting TT. The problem is that if they succeed then it take unavoidable 2 years of industry involvement that will convert any talented and wiling individual into a another industry deadbeat. As the result all contemporary TTs are not made not to serve the sonic demands but to satisfy the demands of marketing campaign that were redeveloped to publicize worthless BS around the TT. 

Anyhow, the side-subject of this topic is a very sad fact that we do not a true knowledge how our top of the line TTs sound in reality and how this or that technology work in them. If you take 20 top-flying of TT today then do we really know how they sound? I do not think so. Those turntables temporary owned by a small group of industry pimps who customary have very bad sound in their listening rooms and who pay mortgages and put kids though colleges by talking about turntables. Also, those turntables owned by a small army of the industry followers – the Robb Reports junkies – who suck in the publicity waves and buy in what they were told. They might be fine people but in term of independent sane audio judgment then are no different than the shit that flow in sewers in accordance with the rules of simplistic gravity. As, the result 95% of top flying TT in the hands of the people who are not able to give evaluation to the technologies  that were used to make those turntables.

A good case to point.  My EMT guy that I told above has also a tope of the line Micro. Over the year we have a number of desiccations: what TT has better bass 927 or Micro. Here is an interesting twist: we did this thinking not to convince anybody else but for ourselves and over the years (!!!) he using both of the TTs realized that he can’t answer this question. Interesting is that I do not agree with my friend’s playback and particularly with bass that he is getting but I very much understand how he feel about hit TT comparing. If criteria of interest is not the superficial BS that need to be delivered to somebody with objective “to convince” but own deep interest on the subject then it is very difficult to find satisfactory answers.  We do not know how our “best” TT performer as we do not have a framework where a nature interest in TT Sound will be exposed to public without any agenda. With TT we are in managed environment where opinions are passed as tools of same not the properly of actual performance.

Therefore, looking at all of it I do not believe in any conversations about TT. I think a TT much be comfortable for a person to use - nothing more.  Everything else is included into the person private thinking about his TT, his sound and how to convert from one into another….

N-set wrote:

Leaving all that unnecessary bitchings and emotions aside  (btw, talking about TT resembles talking abut foundations of quantum mechanics, emotions and flames appear within seconds!), I've been,purely theoretically, thinking if employing 3 idlers or even 4 to drive the platter into that magical floating rotation would be beneficial. Just like it is attempted in some belt drive designs. Garrad 1001, EMT 5027,...?

Anyhow, regarding you idea of multiple idlers rolls. I do not now like it as much as I do not like the idea of multiple direct driver or multiple belts. I have expressed my arguments on the very same subject somehow in the site before, unfortunately the site is becoming large and I do not remember where. I do feel that the idea of the multiple drives is use explicitly for building up more expensive products – there is absolutely no theoretical justification for this with which I would  know and agree.  Suing it I am under presumption that there are no other then theoretical justifications of the multiple drive’s advantages or disadvantages. I do not feel that anyone anywhere conducted any methodologically-properly practical tests to assess the tangible results.

Stitch wrote:

Great idea. :-)

N-set wrote:

The only purely theoretical point which is intriguing for me in the whole multiple drive idea is whether one can achieve a uniform "floating" rotation: the forces perpendicular to the spindle balance out and the spindle rotates without (too much) intercation with bearing's walls. Is it reliably, repeatedly and proveably achieveable under dynamical condictions in practice?

Romy the Cat wrote:

Why do you feel that uniform "floating" rotation is possible only with N amount of drives?

Romy the Cat wrote:

Let look in this deeper. A single drive would it be idlers of belt transmitting moment to platter has errors (slips, bends, elasticity…  etc). Those errors make a platter to reset microscopic backlash in bearing. The minute deviation of speed is not truly a problem but the platter rocking back in force while it clears the micro freedoms between mating element of bearing is a problem.   Now we presume that let say 3 idlers or belts driver the platter at 120 degree and they create more uniform rotation. Yes, the errors of each idler or belt is less critical and now it transmits 1/3 of moment. However, why we are under a presumption that idlers or belts errors have random character. What will happen if idlers or belts errors took place in near same time? We just have no control over it as the idlers and belts are not synchronized.  Now, let see how a single idler or belt work. The force of the moment from ONLY side permanently offset the backlash of the bearing, creating a mechanical biasing of the bearing errors. So, the theoretical conclusion is that a single drive is better.