Direct Drive

Here ya go!

Vincent PHO-8 Phono Stage MM/MC w/ Outboard Power Supply | Audio Advisor

There is nothing wrong with the set up you are thinking about.  It will reliably play records and last for years.  The difficulty for you will be that it will sound inferior to just about and cd player you might listen to so you are kind of setting yourself up to always prefer digital.  You need to know yourself and understand your expectations.  If you just want to be able to play records that may come along and treat the analog as a secondary source then a Technics 1500C and Ortofon Red is just fine.  But it will not, repeat NOT, allow you to hear the full potential of analog reproduction.  Not even close.

Parks Puffin goes for just a bit more new and does have a volume control but I’d like to audition it first.  The Cambridge Audio phono amp is also on my list 

You might be able to find a used Parks Puffin in that price range. 

OK the Technics 1500 is working and I’ve bought a few records. Unfortunately I am having a problem with the phono preamps that I had in storage as they both don’t seem to be working. I knew one was problematic but was disappointed that the other isn’t producing any sound, as it was fine when last used but hey, it’s been in storage for 6 years. The tt has a built in phono preamp-glad I opted for that— so that is what has been used. I also picked up a used Project usb preamp for about $30, as I am intending to digitalize some lps, and it does work but predictably sounds like you know what when just used as a preamp alone, but at least the fact that it works let’s me know that there isn’t a problem with the output of the tt itself.

So using the included pre amp I am impressed with the speed stability of the table. Also these used recordings sound dead quiet. However the volume is meh. I have to push my Cary SLP-3 preamp to its limit to get a volume that is about 80% of my normal listening level.

  So I want a new phono preamp but I have kind of hit the budget at the moment.  I am thinking of something in the 200-$300 range hoping that I can at least get to a normal listening level.  Yes, I have read the threads here that suggest the phono should cost as much as the tt, but reality is intruding.  I don’t see this as ever being more than a secondary source for me anyway.  I am going to ask a bricks and mortar store if they will let me home demo something in that range

The TT > Tonearm and mounting method for these two items are all equally important.

A poor functioning TT will not allow the Tonearm to present to it best.

A poor functioning Tonearm will not show the TT when at its optimum performance to be presenting at its best.

A poorly thought-out mounting method will not enable, either TT or Tonearm, if both optimized in their design and setting up, to present at their best. 

When this Trilogy of mechanical interfaces is produced to a standard that is sympathetic to the optimised function of each.

It then makes sense to concern oneself about the other ancillaries to be used, i.e, Cartridges and the remainder of the Signal Path. 

My experiences have shown myself, that a sub £1000 Cartridge can prove to be as attractive in use as a £4000+ Cartridge when used on an optimised TT > Tonearm Set Up with careful consideration put in place for the Signal Path materials.  

@lewm  Yes, what I wrote was ambiguous. I meant, "I agree with Lew (about TT and tonearm being important) AND TT is most important ...".

@pedroeb  Absolutely. Which is also why some mechanism of keeping the record flat is so important. Vacuum hold-down is effective but cumbersome, but a reflex clamp is just as good for most records.

@ketchup  My tonearm is an air bearing DIY with rock solid shafting and precision adjustments in all directions. The actual fine measurement of azimuth is from a fine scale counter marked in 100 micron increments, but capable of repeating to within 20 microns. Since the beam is 254 mm, resolution is calculated quite accurately by the small angle relation tan ~ sin ~ angle in radians, and 20 microns corresponds to about 30 seconds of arc. Adjustments on this scale are not sufficient to impair horizontality much at all, and so I have azimuth on the fly. Adjustment is secured by a brake.  

@pedroeb 

"Where do I get 3 phase when my house is only single phase? Surely AC motors are asking for trouble."

Two entirely different things.  Phase does not necessarily mean AC, and AC does not necessarily mean sinusoidal.  In these instances we're primarily talking about BLDC motors.

Thanks for agreeing with me, T9, but my point was not that the TT is most important; it was that flippant generalizations, like “differences between turntables…” are not helpful and may be misleading. And of course you can’t leave out the tonearm.

My own tonearm adjusts azimuth to less than 1 minute of arc, and just this evening I found myself changing over a +/- 2 minute range with clearly audible results.  Not many arms can do this, and unless they can, cartridge performance suffers.

@terry9 - How do you measure these small angles and what tonearm are you using?  Isn't any tonearm capable of infinite azimuth settings if it has a rotating headshell (or rotating arm wand for linear trackers) that locks into position?

@terry9

Thanks for your thoughts.

I've been thinking about tone arms with azimuth adjustment as I believe the stylus' axis needs to be perpendicular to the record even if it means the head shell is not at all parallel to the record.

@pedroeb

Three phase is easily obtained by driving a 3 phase motor with a 1 phase, and tapping the 3 phase power inputs. Viola, 3 phase power. But 3 phase is more complicated than it looks, and so is better left alone.

But it’s pretty much academic if you have a two phase motor with a quadrature motor controller, that is, producing sine and cosine. Then run the motor with sine and whatever mixture of sine and cosine gives the smoothest results. Pretty much the same performance as 3 phase with less grief.

And must agree with Lew on this. Turntable is most important, tonearm next, cartridge last. IMO. Anyway, you can’t get close to top performance from, say, a 10K cartridge with anything less than a first class TT and tonearm, say 50K or preferably more. My own tonearm adjusts azimuth to less than 1 minute of arc, and just this evening I found myself changing over a +/- 2 minute range with clearly audible results. Not many arms can do this, and unless they can, cartridge performance suffers.

“Differences between turntables often comes down to the cartridge.”  The same cartridge will sound different in a different tonearm on a different turntable.  The same turntable will sound different with a different tonearm and cartridge.  These variables are not trivial. And your general statement leaves out the tonearm entirely.

A local dealer dealer just mentioned the Fender x MoFi PrecisionDeck Limited Edition Turntable is in stock.

For looks alone Fender's iconic Sunburst is truly amazing.

Differences between turntables often comes down to the cartridge.

In this case it is the Mofi MasterTracker Cartridge, which is almost 25% of the total cost.

 

@dover 

"Any of the vintage use DD's use 3 phase motors ?"

This caused me to try to think for a moment of one that isn't at least three phase, and I'm coming up empty. 

For vintage DD tables I look no further that Victor, better known to most as JVC.

My TT71 motor drive unit is a beautifully crafted and precise operating DD table that uses a DC motor. It's a 12 pole, 24 slot DC brushless motor with a frequency detection circuit that uses a 180 slot frequency generator yoke with a magnetic disc and a printed circuit board with 180 coils printed on it. Needless to say, speed is very accurate and wow and flutter is very low.

Most folks don't realize that Victor invented the modern quartz locked direct drive motor system. Victor was a engineering company that shifted it's focus from audio to video in later years and became leaders in that field as well. Victor supplied motor drives to other companies as well, Micro Seiki being one of them.

BillWojo

As I said. "The new Technics" this includes the SL-1200GR. slotless, coreless, 3 phase. Some versions available right here in NZ for $3000. 

The reference class Technics SL-1000R is available here in NZ for $31,999 ( Under US$20,000 ) 

The Pioneer P3 and the Victor TT-101 with slotless and coreless motors, also appear to be 3 phase, but I cannot be sure. Same would apply to the big Sony's 

If you widen the category to just 3 phase...pretty much every Technics DD ever made.

Where do I get 3 phase when my house is only single phase? Surely AC motors are asking for trouble.

DD TTs using three phase motors. The new Technics, the SAT, VPI. I'm not sure about the NVS and the Monarch, but would be surprised if they weren't three phase, given their quality. Then of course there is the motor I build and install into my K3 design 

@richardkrebs 

So none of the 3 phase motored DD TT's are available under US$40k.

Any of the vintage use DD's use 3 phase motors ?

It would appear that the 3 phase argument you proposed is only as relevant in as much that only about 0.0000001% at most of DD TT's ever sold actually use a 3 phase motor. That would mean statistically your argument is irrelevant.

A heavy platter like that used on the Final Audio, will lower the rates of deceleration, acceleration. High inertia reduces the magnitude of speed changes, it does not eliminate them. 

The connotations of the words "immediately and "suddenly" aren't appropriate and I did not use them.

DD TTs using three phase motors. The new Technics, the SAT, VPI. I'm not sure about the NVS and the Monarch, but would be surprised if they weren't three phase, given their quality. Then of course there is the motor I build and install into my K3 design 

The platter will slow down and a belt, thread, tape or rim drive, would slingshot the paltter up to momentary over speed once the high stylus drag reduces.

Thats funny.

My TT platter is 26kg, that you would think that immediately after Horowitz has banged out a C1 fortissimo on his Steinway, that the 26kg platter would suddenly take off into overshoot like your direct drive software going wonky is fanciful.

@richardkrebs 

better DD TTs use a 3 phase motor,

Can you provide a list of any DD TT's that use a 3 phase motor.

I just knew I should not have hit that bee hive with a stick😊

Correct, it is not cogging, as Lew and I have already explained.
“ the problem is pulsing”  let’s get this out of the way..,,
An 8 pole motor would be 2 phase. This is not a linear torque design, better DD TTs use a 3 phase motor, designed for sinusoidal back emf. These synchronous motors are inherently linear torque. They do not pulse 
Any deviation from linear torque due to manufacturing tolerances is called torque ripple. In good three phase motors, this is vanishingly low, but not zero. Nothing is perfect. Further, today’s sophisticated controllers can now “look” at this ripple and mitigate it in real time. Thus calibrate the controller and motor pair. Further this ripple for say a quality 18 pole motor running at 33.33 is sub sonic, well below 20 Hz

Consider what happens when you replace a compliant belt with a material that does not stretch. Since the motor is running much faster, you are now injecting the motors torque ripple into the platter. It’s frequency right in the audio band. 

Monaco improving their error correction is audible not because it is improving the motors no load speed accuracy but because it is improving how the drive reacts to platter speed changes due to the dynamically induced load caused by stylus drag. 
The fact that this can clearly be heard should concern some here who champion alternate drive architectures. Such drive systems are “blind” to these real time platter speed changes. 

As I said earlier, making a drive speed stable under dynamic load conditions is insanely difficult.

Making a drive speed stable under constant load is relatively easy.

cheers 

Actually its not cogging.

The essence of the main difficulties with DD is derived from the fact that a direct drive requires a motor to run at 33rpm - the gearing is 1 to 1. In the old days ( 70's ) it was very difficult to control motors accurately at such a low speed.

The problem is pulsing.

If you run an 8 pole motor @ 33rpm there are effectively 8 poles per revolution ( of the record ).

For a non direct drive, say using the same 8 pole motor at 250rpm ( with gearing either via belt/thread plus pulley or other ) then there are 60 poles per revolution.

If you translate this to a merry-go-round - imagine 8 people pushing it versus 60 people pushing it - which model is smoother in operation. Especially if the "pushers" are uncoordinated, statistically the 60 push model would be much smoother by some margin.

The other issue is error correction.

If you think you cant hear error correction then look no further than the Grand Prix Audio DD turntables.They released a DD with state of the art error correction software using latest computer chips only a few years ago  - "unparalleled speed accuracy " they said.

Well, several upgrades later including some based solely on new updated software algorithms, the sound has miraculous been improved considerably - as confirmed by reviews and owners.

Conversely the main issue with most belt drives is weasel motors, and elastic rubber belts. Replace the rubber with silk thread, which has virtually zero elasticity, a decent motor and inertia in the platter and you get excellent speed stability.

I note the new Kuzma R & M now use rigid polymer belts with a motor that has been designed expressly for this purpose. 

Idler drives can achieve good speed stability, but only if they use decent size motors. My view is the "drive" of idlers" is due not only to the removal of the stretchy rubber belt, but more importantly most of them use decent size AC motors with bags of torque compared to the usual cotton reel sized motors used in most belt drives.

One of the inherited conditions offered through using a DD TT.

One that is for myself quite satisfying. Is that when adopting a DD with Servo Motor Control, concerns for the Speed Control fall away.

In my long period of using other Drive TT's somewhere into the owner ship the accurate speed control becomes a subject that is required to be investigated.

It is soon learned that a Speed Control Device to be added to another Drive TT, whether Idler Drive or Belt Drive can easily amount to the cost of DD TT that has the Speed Control built in.

If Speed Control is a concern and budget is limited, a DD TT is not too bad a place to be in selecting a TT.  

Clear thinker, At least keep your prejudices vis a vis DD turntables straight.  The phenomenon you describe and object to is not at all analogous to “cogging”. Cogging is an issue for all iron core motors; look it up on Youtube. Arguably the coreless motors used in some of the finest DD turntables do not exhibit cogging at all. You are objecting to the action of the servo mechanism to maintain constant speed.  That is not related to cogging.  On the other hand, most modern high end BD turntables incorporate some sort of mechanism often involving servo control of speed, to the same beneficial end. A few posts up this page, you can find Mijostyn bragging about what is essentially feedback/servo speed control of his SOTA Cosmos.  I use the same devices made by Phoenix Engineering for my Lenco; the improvement is very noticeable and I would not be without. 

@clearthinker 

I think that we need to step back and look at drive alternatives a little more accurately. A well tuned PID controller will not constantly speed up and slow down, provided the motor controller architecture is well designed.. The phenomenon you mention does exist in poorly implemented systems and is called hunting. Cogging is a characteristic of some motors due to their physical build. (Slotless, coreless motors, properly made are zero cogging and have vanishingly low torque ripple.) 

Synchronous motors, widely touted in these parts for belt drive and rim drive, under a varying load, say playing a record, do hunt about their average if you measure them with sufficient granularity. Synchronous motors therefore exhibit the very characteristic you rail against in a DD system.

The answer to smooth speed is only partly helped by high inertia. What matters more is the frequency response of the drive. A function of the platters inertia and the motor's torque. Then there are a multitude of other factors to take into account when designing a drive system, no matter what type of architecture you choose.  Please view the youtube link here. Note how quickly the arm, which obviously has mass, is pulled across the tank and in so doing how it lifts the weight in the glass bottle. At times the arm is held for some time against the edge of the tank. Inertia won't save you under these conditions. The platter will slow down and a belt, thread, tape or rim drive, would slingshot the paltter up to momentary over speed once the high stylus drag reduces. A properly implemented DD will also do this, but at a much lower magnitude.

I realize that I'm opening Pandora's box here and I'm not looking for a debate on the subject. We all have our favorites  But please look at the video and then consider what would be the best drive architecture to counter this dynamic load. It is an insanely difficult task to control a platters speed under dynamic conditions. All drives have their pros and cons. I happen to believe that modern DD is superior at this. of course others disagree and that's just fine with me.

Скатывающая сила как измерить - YouTube

@dover and @testpilot are not wrong.

DD motors are controlled by computer speed measurement and are constantly being speeded up and slowed down to achieve the designer's aim of a perfectly stable speed.  In the event they cannot achieve a stable speed because they are never running at the same speed, aka cogging.   @billwojo the evidence is in the engineering specifications of DD turntables that state they have constant speed monitoring and adjustment.  Written in black and white.

As Dover says, this is analogous to digital control of digital sources where clock error is responsible for perceived speed instability known as jitter.

The alternative approach of using high platter mass and Newton's first law to maintain speed consistency through inertia is a far better approach.

OP,

Wow. Sorry to hear. I grew up in a suburb of Chicago.

I still remember driving down and trying out my first car… used. Bought it, ran… until the battery ran down. That is when I learned what the pulley in the truck was for… but could not be reinstalled. Several huge investments in major engine repair later… well, finally gave up and my parents helped me buy a new car… $1,999.

A doberman? Not a good sign.

Hopefully, this is not a story like that.

@mijostyn - the energy dissipated by the vibration of a very low mass arm onto the stylus (like a Rega) is less than the vibrations coming up from the motor through a platter, no matter how heavy. It is 2 different philosophies.

I would be interested in measuring the actual vibrations at the record while it is spinning if possible, both with and without the stylus on the record, which takes into account the platter mat (or isolator in my case). Probably pretty hard to do, so the best you can do is listen and Rega's come out very highly regarded.

As an example to the light platter/plinth and minimum force/energy motor extreme , take a look at Rega's Naiad. That is what the P8 and P10m are based on. It is absolute minimalist. Expensive at about $40K, but that's the philosophy. Of course, it should be isolated on a wall shelf or a platform like a Townshend (or both). To me, it is the ultimate quiet table. Roy Gandy states correctly that a turntable is simply a vibration measuring machine and he strives to create the lowest internally generated noise possible.

A direct drive transmits motion to a system or object requiring actuation without the use of any further mechanical components.

How did you set the tracking weight? Did you zero out the weight before setting the weight (start where the arm "floats" level)? Did you use a scale? 

Received the table but unfortunately I had thought the Seller was going to do more set up.  I was able to mount the cartridge but I can’t get the tone arm weight right.  I have followed the procedure in the manual several times.  First I adjusted the weight at the end of the tonearm so the arm looks horizontal.  I then dialed in both the stylus weight and antiskate at 1.8, which is what Ortofon recommended.  Still, the arm goes up at a 45 degree angle when released from its restraint.  After repeating this a few times I quit.  Today is Sunday so I will call the seller tomorrow but they haven’t been to CS Friendly so far.  They are located in a really non descript area and I was greeted at the door by a manager holing on to a huge, snarling Doberman .

"the presence of a large oscillating magnetic device right under a very sensitive magnetic device."  You're talking about the potential for EMI from the motor affecting the cartridge.  Why not just say it that way?  As I have mentioned many times, the platter is an effective shield vs EMI, in a well designed DD.  In addition, for DD turntables that use coreless motors, the coreless motors used are all fathered by the original Dual-designed coreless motor, which looks much like a discus used in track and field.  In latter day iterations of that motor, the works are encased in a metal that serves also as a shield and furthermore the radiation from that design is laterally, not in the up/down direction.  The proof of the pudding is in measuring EMI at the platter surface while the turntable is operating.  I've done that. To the level of sensitivity of my meter, nothing is seen above background.

@lewm, Correct, the belt is a first order filter so the attenuation would be 6 dB/oct. But, by the time you get up to the vibration generated by the motor nothing gets through to the platter. 

The motor platform or bracket is attached to what Sota calls the cover. The sub chassis which holds the platter and tonearm is isolated from the cover by damped springs with a resonance peak at 2-3 Hz vertical. Sota does not specify horizontal resonance which is certainly higher perhaps 5-6 Hz. The Superiority of the MinusK platform is that it's horizontal resonance is almost as low as it's vertical resonance. The problem with the MinusK  is that it can be a bitch to handle a turntable on it because it is very floaty. You have to be very gentle to keep it from bouncing. The Sota on the other hand is a delight to handle. You can use the cover to brace your hand when you cue the record. You can drop the dust cover and nothing happens. In order to get the record to skip you have to hit the turntable on it's side hard enough to move the entire turntable.  

The next advantage of the Sota is that it uses a magnetic thrust bearing. It is the thrust bearing that generates the most noise as it is subject by far to the highest pressure. 

My real problem with direct drive turntables is the presence of a large oscillating magnetic device right under a very sensitive magnetic device.  Speed wise they can be very accurate. Noise depends on the quality of the bearing. I know of no direct drive table with a magnetic thrust bearing. In the end, stable, accurate speed is stable accurate speed by whatever means. I prefer my motors as far away from the cartridge as is practical. It is an instinctive preference I admit. The requirement for a suspension is not instinctive. I can demonstrate the superiority of suspended turntables to anyone in just a few minutes without playing any music.  

@sokogear , I am a proponent of Schroder arms. I have one but, the CB is $1000 more than the 4 Point 9 and I was trying to showcase the Sapphire in the least expensive combination I would find expectable. 

Making sense is an assumption. Assumptions are the mother of all F-ups. The record vibrates the stylus, then there is Newton's third law. To stop the record from resonating under the stylus that "energy" has to be dissipated in a much heavier mass by pinning the record as firmly as possible to that mass which in this case is the platter. With the record firmly fixed all that energy goes into moving the stylus which is also connected to a much heavier mass, the cartridge and tonearm which in turn are connected to an even heavier mass, the turntable.  I think the vast majority of turntable aficionados agree that the record should be firmly pinned to the platter and most of the high end turntables have a mechanism to do this.  

@mijostyn - gotcha. I thought the Sota was around $4K. Also thought you like Schroeder arms. You should be a turntable market analyst/consultant. BTW the record clamp/device I asked you about works nicely, really for thinner or warped records - the Hexmat Molecula. Really it is the only option for light. short spindle tables that strongly discourage putting any weight on the platter. Also, their record isolator (mat), the Hexmat Eclipse, also is an improvement over any other mat I have tried (felt, polymer-Herbie's, and rice paper). They are pricey items, and they make a less expensive isolator, the Yellow Bird, but compared to the price of a good TT, worth considering. I know you are the heavy platter, stick the record to the platter proponent, but I think the isolation of the record barely touching the platter (1 sq. mm surface area makes sense, and more importantly sounds nice.

Ketchup, I take the bearing as a given for any turntable of any type.  So there is no special problem of a bearing in a DD type.  All platters ride on some sort of bearing.

Mijostyn, I don't know precisely how a Cosmos is constructed, but I do know that  SOTA have improved upon basic design of a suspended BD.  When you mention a "separate platform" for the motor, it must nevertheless be either suspended along with the bearing and platter or fixed in space.  Which is it? How is the platform isolated from the subchassis or shelf?  I'm just curious, not contentious.

You wrote, "Above that frequency such as at pulley speed all vibration is absorbed by the belt. Nothing gets to the platter."  Come on.  Nothing designed by men is that perfect.  The belt is a filter with a certain cut off frequency and rate of attenuation of mechanical energy.

@sokogear , Why? A Sota Sapphire with a Kuzma 4 Point 9 is $8000. The Thorens is 1/2 the price. 

@mijostyn  - I was surprised to hear you prefer the Thorens over the SOTA that you have gushed about in the past.

 As in a classical motor, the rotor is driven by the stator due to electromagnetic interaction.  Nothing physically touches the rotor (in this case, synonymous with the platter) in a motor

What about the bearing?

@sokogear , Yes, that is what I said.

@lewm , accepted. I know exactly what speed my platter is running at to 1/1000th of an RPM. The turntable tells me in bright green LEDs. The motor is not mounted to the sub chassis. It is mounted on a separate platform that places the pulley, belt and thrust bearing in the same plane. Under normal circumstances there is no movement between the motor and sub chassis and no belt slippage at all. The belt itself is a filter, a low frequency filter. Below that frequency everything moves together such as if I lift the turntable up and down slowly. Above that frequency such as at pulley speed all vibration is absorbed by the belt. Nothing gets to the platter. 

@mahler123 If you possess an indelible recollection of a very good impression left from experiencing a DD TT in use and find the thought of using DD as a Turntable an attractive idea.

The chances are that there is not too much more to do, you have discovered the TT Drive that one can Wed themselves to.

Why not see if you can create an opportunity to share in the experience once more, the outcome might be that ’socks might struggle to remain on’.

I have a history that is loyal to LP as a Source. I am deeply rooted in using a LP as a source material and did not become a DD TT user for many years.

Belt Drive was the first motor drive and was in use for some years, Idler Drive Superseded the Belt and remained in use for many years, and now DD is the TT of choice, and I won’t be going back to the other drives as the main motor in use.

I can still use an alternative motor drive, but mainly put one to use occasionally, for nostalgia and sharing the experience of using one with others.

Digital arrived much later for myself, and I am now at a place with it, that is very satisfying. CD has of recent years, proved to be a very good source material; I have no concerns for it being in partnership with the LP source.

@chaskelljr2001 - you match the phono stage to the cartridge - it has nothing to do with the turntable. I have the Sutherland Insight LPS and really like how quiet it is, and it's very straightforward design. Matches nicely with my van den Hul One Special. Plus Ron Sutherland is a great guy and will be glad to talk to anyone - he picks up his phone! It's a one man company with the manufacturer local to him so he can insure quality. He talked me through the install of the LPS, (which I got directly from him) in my Insight after I got a nice deal on a basic used one (under $1K). I couldn't believe the time he took with me for a $350 purchase.

At entry-level, I would start with a Technics SL-1200 Mk2 (one that was not used and abused by club DJ's), there are some out there that were not used by a DJ and start there, and you should get one of those for $500.00 or so, and start with an Ortofon 2M Blue and go up from there (a Denon DL103 or better comes to mind here).

Further up the food chain, I would then hunt for a Technics SP-10, use whatever tonearm that sonically pleases you, then start with a Denon DL Series Phono Cartridge and go on from there.  
 

Don't forget not skimp on the phono stage while you're at it.  I do like the Sutherland Phono Stages.  Maybe overkill for the SL-1200 Mk2 depending on which model you select.  Now, with an SP-10?  You're good then.  Don't want to spend a King's ransom on a phono stage (which I don't), then I would look for a PS Audio GCPH that's also well kept.  Those were $1,000.00 when they were brand new, but you should be able to find one for $500.00 or less now.

Good Luck and Happy Listening.

--Charles--

Whatever Harry Weisfeld wrote on Audiokarma, it cannot be accessed unless one is registered over there.

Sunnydas1, what is your point? In a direct drive turntable, you can think of the platter as the rotor part of a typical motor.  As in a classical motor, the rotor is driven by the stator due to electromagnetic interaction.  Nothing physically touches the rotor (in this case, synonymous with the platter) in a motor.

From Harry Weisfeld

https://audiokarma.org/forums/index.php?attachments/c74f09c9-9ca1-43ba-9c35-a8dd0e307582-jpeg.2581917/