2020 update : JC Verdier La Platine

The undisputed aspect with the La Platine is the magnetic bearing, allowing the platter to rotate while being decoupled. The idea was what attracted me. Having acquired it, it is the execution of the idea that truly intrigued. The metallurgy and the assembly involved are its distinguishing qualities. 

The drive system was the second aspect that required study. Through informed opinions by members of this forum and experimentation, I have come to the following conclusion: the drive material with the least surface area is the best. This translate to the least amount of friction produced by the drive material. And this preserves the inherent braking action of the platter to counteract stylus drag. Thread drive therefore is the best.  Of the threads used, pure silk from YLI was the best, the stock linen ( ? ) thread the least preferred. The silk thread produced a more 'continuous' soundstage with more 'air ' around instruments.

The motor is presently the most troubling aspect. And it has to do with speed stability. I performed a test suggested by @ct0517 observing the number of rotations before the platter comes to a complete stop by firstly turning off the motor and secondly by cutting the thread while still running. This test confirms that the platter is not in a state of free, un-restraint rotation. A braking action is designed into the platter shaft assembly to counteract stylus drag. I then performed the same test, but this time with a high torque Jasmine motor. The results are very similar. This tells me that  a change in motor would not disturb the inherent braking action of the platter. I believe if one were to change a motor system for the La Platine, it has to be compatible with the thread drive. The spindle head of the stock Philips, low torque, motor is coming into contact with the same thread as on the platter side. While the low friction on the platter works to preserve the braking action, the same low friction on the spindle head does not work to preserve speed stability. The stock motor has a different setting for thread and belt drive. The original motor design acknowledges that different material drive with require a different electronic control. And I feel it is the electrics of the motor assembly that is at fault for speed instability. I somehow think that a motor with a servo system works best. But in the thread drive ultra-high end Japanese CS Port Lft1 turntable, it specifically uses a high torque non-servo motor. On the motor front, I am still researching. However, this in no way affect my admiration for the TT and my enjoyment of music produced through it.

There is one other aspect that I have read very little about: the plinth. I have the black MDF plinth. I would like to know more about the Granito plinth. Somehow the combination of concrete, raisin, and stone chips doesn't seem to be a good resonance damper. I would like to be enlightened. 

Interesting read. I have a Transrotor Apollon with 80MM platter and Transrotor Magnetic Drive (TMD) drive assembly. The spindle bearing is some viscous oil fluid, and the platter is spun by three servo controlled motors with belts. Speed drift is a constant with be,FS when they start wearing, but otherwise, it is a stable platform and very robust. Prior to the TMD my platter would spin until it lost rotational inertia. Now, with TMD, it slows down after a few rotations before coming to a complete stop. That is due entirely because of the TMD. Is the braking you speak of on the motors happening during music playback, or only when spinning up or down? 

This is my email written long time ago to my friends in Toronto. They are members of GTAA audio group and many members have La Platine and share their experience with this amazing TT between themselves. I wanted to share my thoughts and experience with them and I hope you can find something helpful for you.
In original mail there were many pictures but I do not know how to pot it here.

""" I am very grateful to you and all of your friends who spent countless hours helping to improve and tweak the Verdier. The Verdier is an amazing turntable, even in stock form it is one of the very best available. Once tweaked, I believe it to be one of the finest turntables available at any price - beating my reference turntable Versa Dynamics 1.2. One of the strongest features is its unique and effective design. Design is one of the most important aspects of any HiFi component. You can extensively tweak a mediocre design and find that a properly designed, less expensive and simpler component will be vastly superior. Because of its brilliant design, La Platine can easily be tweaked to achieve analog nirvana. I have listed my improvements below:

1. Motor – one of the options was the old Teres motor. Problem is, it’s out of production and Teres didn’t respond to my emails. Furthermore there are difficulties with the Teres motor in regards to tape placement on the pulley. Placing the strobe light under the platter was another issue. I also considered some more expensive options available in the marketplace. After speaking with several respected members of the audiophile community I decided to go with the stock Verdier motor. The stock motor is excellent especially with the following improvements:

a) I made a battery power supply using a marine battery and utilizing a DC to DC converter. The variance in output was excellent +/- 0.02Volts. The Internal AC connection was bypassed including the on/off switch.

      
b) The stock pulley was replaced with a custom Delrin pulley to accommodate ½” Mylar tape. The pulley must have convex sides, bulging out in a way to keep the tape centered. Once properly placed it is extremely easy to put the tape on it, it can be accomplished in less than five seconds. The pulley was made to perfectly fit the Verdier motor.


2. Using 1/2” Mylar tape instead of string or thread

Using tape greatly improves speed control. Greater speed control translates into improved dynamics and tonal color. The image below shows the Feickert Platterspeed measurement on my Verdier.




          



3. Plinth Support – this is a big question- to use the original springs or not? Two very prominent TT designers told me that it is not good to use a spring/suspended plinth with a design like the Verdier. Their contention is that it is almost impossible to get the correct speed due to the almost constant movement of the springs. To compound the problem, changes in room temperature and humidity affected precise plinth leveling. With all of this said, the original springs produced excellent results in my system. It resulted in a beautiful lower midrange which shone when playing small jazz ensembles and excelled at reproducing the human voice.

I tried everything, Walker and Mapleshade spikes, ebony cubes, carbon cubes, Boston Audio cubes, roller blocks, etc. Springs still sounded the best, until I tried the Stillpoints Ultra SS. I typically never liked the Stillpoints in the past. A very good friend of mine is a Stillpoints dealer so I previously had the opportunity to try them under all of my equipment (speakers excepted). Didn’t like them in that application. Their effect was to increase the resolution but also lifted the tonality upward so that it sounded more HiFi. Nothing wrong with that, 90% of audiophiles would love it, but it wasn't generating the organic sound I was trying to achieve.

At this point I was ready to order the Vibraplane to try under the turntable. By pure coincidence, I ran into my friend, the Stillpoints dealer who suggested I try the Stillpoints under the table. I tried it and the results were fantastic. Increased dynamics, greater frequency extension, more detail, nicer texture, a great improvement over the springs. This was not a subtle improvement, it was dramatic.

The orientation of the Stillpoints makes a considerable difference. In my system facing the tips up resulted in a huge soundstage but I lost body and texture. Facing down gave me the more satisfying results.

Two additional things I got from the Stillpoints were:
a) even greater speed control
b) the ability to support two heavy tonearms with copper/ebony boards without any problems in regards to plinth leveling.


4. Copper/ Ebony board for tonearm - I liked it from the start so I did not try anything else




   

5. Spindle ball touching the platter - there is a lot of discussion regarding this topic. Opinions are equally divided, pro and con. I have tried both and preferred the results when the ball is touching he platter. I purchased the tungsten carbide ball with the 10mm radius. I noticed dramatic improvements in the bass and overall dynamics. The bass became much deeper and tighter while the dynamics were on a different level versus the stock Verdier. No perceived penalty, just the a aforementioned improvements. The trick is to have very little of the platter weight supported by he ball, just enough to drain the lower frequencies. The rest of the weight - I would guess approximately 95% is still levitated magnetically.The same principle is used by Continuum Calibrum Reference turntable. You can easily test both options, placing small rubber washers under the lower magnet will quickly revert the levitation to purely magnetic.


6 .Record Mat – I suggest this is very system dependent. In my system I tried the Millennium M-LP Carbon, the Micro-Seiki Copper, the Boston Audio 2 and the one I ended up preferring, the Merryll Williams – GEM Dandy RCC mat. Carbon was too HiFi for my tastes, the GEM Dandy was very well balanced with a nice natural sound.

Please note, all of these findings are based on my tastes, preferences and my system. You may get very different results in your system. """"

In meantime I bought TechDAS AF-3 Premium but I still have Verdier and I can compare it to any TT on the market nowadays

Albert,

The spindle head of the stock Philips, low torque, motor....

The Verdier uses a powerful, High torque, low inertia, core-less DC regulated motor.

And I feel it is the electrics of the motor assembly that is at fault for speed instability.

I somehow think that a motor with a servo system works best.

Here's a logical explanation from Charles Michlin (Azzolina Audio): "In the era when the Verdier controller was developed the LM317 voltage regulator was probably an advanced device. However today there is a greater understanding of motor control. A motor acts as a generator in operation and this back EMI causes error in controllers like the LM317. As a result they fall in and out of regulation erratically. There are newer chips designed for motor control which are immune to this problem. There are also circuits of greater sophistication which can self correct speed variations without the complications and problems of closed loop feedback."

@lbelchev Thank you for pointing out my mistake. I believe it is not the only one I have made. See below.

@audioquest4life I had thought I understood the braking action. Because of your question, I took a look again at the comment on a past thread by @ct0517 :

"If you actually cut the thread with scissors I am willing to bet it stops in much less than 7.5 revolutions as it is the same friction principle as the magnetically levitated Platine but using oil instead"

The comment described first turning off the motor and observing the number of rotations before the platter comes to a complete stop. It requires 7.5 rotations / revolutions. This is consistent with what I observed on my TT, anywhere from 7.25- 7.75 revolutions. 

However, when I remove the thread with the motor running ( i didn't actually cut the thread ), I observe about 20 + revolutions before the platter comes to a complete stop. The comment above seems to indicate that the platter should stop with maybe 3-4 revolutions and that would supposedly show the 'braking action'. My TT did not behave as such. The 20 + revolutions on my TT is more likely the platter coming to a stop due to a natural loss of rotational inertia, rather any 'braking' action of the spindle and shaft.

So in short, I am realising that my TT did not exhibit the supposed braking that was observed by others. But then again, having such a heavy platter come to a complete stop within 3-4 revolutions while in free rotation would indicate some heavy forces acting on it. That force is not present on my TT. I must have made a mistake in proclaiming that I have understood the braking of the platter on a La Platine. I may again need to be enlightened.