Direct Drive vs. Idler Drive vs. Belt drive


I'd like to know your thoughts on the strengths and weaknesses of each drive system. I can see that direct drive is more in vogue over the last few years but is it superior to the other drive systems? I've had first-hand experiences with two out of the three drive systems but looking to learn more.
21192e21 5d00 4ded bea1 72869e5cf35dscar972
There are many threads here that debate this. There is no consensus.

As with so many things in audio, it's best to listen and decide for yourself.
Oh lets do MC vs. MM vs. MI again too.
Dear @scar972 : As cleeds posted, first hand experiences is the solution.

In the other side please make your work and brose all the information here in this forum about. Exist " hundred " of threads in that same subject.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
The issue is you need a powerful drive. Direct drive easily has the best speed stability (Technics makes the most speed stable machines in the world and their drives are pretty powerful). A powerful idler drive can easily dust a weak direct drive or belt drive- a powerful belt drive can easily dust a weak idler drive or weak direct drive.

This is why you see a following around certain vintage turntables- all of them have powerful drives- the Technics SP10, the Garrard 301, Empire, Lenco and the Thorens TD124.


The problems with the vintage machines is usually a poor plinth design which does not take into account the effect vibration can have on the sound of the machine, and crude tonearm performance (solved by installing a modern arm). If the designer has done their homework, the plinth (and platter) of the ’table will be quite dead.


Another serious variable is the platter pad- it can color the sound since there is resonance in the LP itself when the stylus tracks it. If this is going on the LP can ’talk back’ to the cartridge. A good platter pad can make all the difference and this is a left out variable in the discussion of which drive is better!! A good platter pad will simultaneously damp the platter and silence the vibration in the LP; this has to be done with a platter pad that has the same hardness (durometer) as the vinyl. In that way energy from the LP is absorbed and not reflected back the the LP. If this is all correct, it will be very hard to hear the stylus tracking the groove with the volume off.

None of the vintage machines had anything other than a joke for a platter pad. For that matter most modern platter pads are no better. IMO this is the least understood aspect of LP playback.
Post removed 
atmasphere, thank you!
Do each drive system have a certain sonic character of its own, I know it’s often said that idler has more drive, bass, etc. Does DD have a sonic character? What is your ideal platter pad material?

There are new people to the forum every day that can/may offer new insight, so I think it’s okay to rehash old topics every once in a while, it keeps the forum going.
this question.....how the three drive approaches might sound different, guided me this last year to add some turntables. i wanted a top level example of each drive method. and then top arms and cartridges too. you can look at my system page for details and pictures.

i have owned a direct drive tt; the Wave Kinetics NVS, for 9 years (and previously owned the Rockport Sirius III for 8 years, generally viewed as the top direct drive turntable ever).

slam, scale, authority.

last August i purchased the Saskia model two, an idler.

PRAT....flow.....tonal weight......timbre.....focus.

then in November i purchased the CS Port LFT1, an air bearing, string/belt drive.

space, detail, liquidity, nuance, decay, holographic.......truth.

and the answer is that these drive differences do play out in musical connection/synergy terms. and i do choose turntables somewhat based on the music or mood i’m in.

so far my favorite turntable seems to change from week to week and i really enjoy them all. i’m happy i made this investment in vinyl truth.

and the last point i will make is that execution is way more significant in ultimate turntable drive satisfaction than dogma. i choose these three turntables for the level of execution of their designs. they each compete with the very top level of their drive types.
I’d like to know your thoughts on the strengths and weaknesses of each drive system.

Direct drive is direct. With an accurate enough clocking system, fast enough correction system, and a motor with a fast enough torque response, direct drive can maintain much higher speed accuracy than any of the others. The problem is all in what constitutes "enough". A good example if you want to get some idea of that is to read up on the Onkk Cue.

The weakness of direct drive is the challenge of dealing with vibration issues and motor smoothness (cogging) all of which are solvable, the question being at what cost. This is the one everyone leaves out, when in fact its the one that matters most. Its almost a complete waste of time to talk about the strengths and weaknesses while leaving cost out. Why do you think so many tables use acrylic and aluminum, and so many speakers use MDF? It ain’t because of their strengths and weaknesses. Its because they are cheap!

All the others, idler wheel, belt drive, are all trying to do the same thing. A belt is great for isolating motor vibrations from the platter. But it does that by stretching, which introduces speed variation, which is bad. Also the main reason for using belt drive is it lets you get away with a noisier motor that vibrates more. Well then the motor needs some kind of suspension to keep it from vibrating the plinth. And round and round you go playing with elastomers trying to get the right mix of vibration control with speed stability. All because its cheaper this way than building a proper motor.

Idler wheel is merely a variation on a belt. A variation that adds a bearing. Its crap, which is why it was so common early on and so rare nowadays.

The one you left out is rim drive, which is of course the best most cost effective solution, as why else would I have chosen it? https://systems.audiogon.com/systems/8367

Okay technically Chris Brady chose it. But technically technically it was a collaborative project of advanced audiophiles a sort of co-op called Teres Audio. So there.

In truth no one can say any one of these is the best, because this is a case of implementation being more important than technology. That’s why there are plenty of examples of great tables that use all these designs. That’s why once again the tech just ain’t all that and what counts is not can you figure out which tech is best but can you listen and hear which one sounds the best.
It appears Mike and I were writing at the same time. Lol! 

His experience perfectly illustrates what I was saying. Its possible to have great results from all of these designs. Look at it this way. If you asked a hundred engineers at least 99 of them would tell you the worst place you could possibly put an engine is way out back behind the rear axle. 99 out of a hundred will tell you that, and the one that doesn't flunked out of class. Yet the rear engine Porsche 911 has been voted worlds best driver's car by more magazines over more years than any other car by far. 

Sad to say Mike has no rim drive example. Oh well. Always room for one more, eh?

Mike, It is interesting to hear from you on this subject.  About 7-10 years ago, you had 3 turntables set up.  One was a tweaked Garrard 301, another was a Rockport Sirius, and the third was a Technics, as I recall, eventually replaced by a Dobbins Technics and then by Dobbins' The Beat.  Have I got that about right?  You were my guru on this subject. Based on your posts and those of some others, I got into experimenting with different drive systems myself.  Having never owned anything but belt-drives, I felt that I knew what they do, up to the price point that limits my selection.  So I acquired a Lenco and highly modified it, and eventually an SP10 Mk3 in slate+wood plinth, a Kenwood L07D, bone stock, a Denon DP80 in slate, and a Victor TT101 in a massy wood and aluminum damped plinth.  Again, I had to play in the cost area that is compatible with my level of affluence.  It has been a very educational experience.  I now run two turntables feeding one system that drives Beveridge 2SW speakers and three turntables feeding my main system that drives a pair of electrically modified Sound Lab 845PXs. It's wretched excess but fun to listen to the same LP interpreted several slightly different ways by the different turntable/tonearm/cartridge combinations.  I must say the highly tweaked Lenco (with input from Win Tinnon) holds its own quite nicely vs the 4 direct drives, and I firmly believe these turntables outperform belt-drives under $10,000 that I have heard.  However, a neighbor had a Dohmann Helix turntable with the built-in Minus K suspension.  That is a way more than $25,000 belt-drive that made me feel a bit of lust.  Or I should call it curiosity to try it in my own systems.  But that isn't going to happen because of cost.  Anyway, it's interesting that you decided to go back to having multiple turntables, after having been happy with the NVS for so long.  Carry on.
Sad to say Mike has no rim drive example. Oh well. Always room for one more, eh?

........and the Dodo bird is extinct for a reason. :-)

just kidding. Chris Brady’s turntables were enjoyable to listen to. and he was a good guy too.

seriously though, the rim drive and idler are the same concept turned inside out. again.....execution of those two similar 'high' leverage drive approaches is much more significant than the dogma of outside or inside.
@lewm

Mike, It is interesting to hear from you on this subject. About 7-10 years ago, you had 3 turntables set up. One was a tweaked Garrard 301, another was a Rockport Sirius, and the third was a Technics, as I recall, eventually replaced by a Dobbins Technics and then by Dobbins’ The Beat. Have I got that about right? You were my guru on this subject.


thanks Lew. and right you are. but back then my collection of turntables (other than the Rockport and NVS) was at more modest price points. i enjoyed my NVS these last 9 years, but decided to invest in a top level belt and top level idler as i found that the music was not ideally served by one drive approach. and it’s been great fun and musically satisfying getting back to having choices when playing vinyl.

the belt drive and idler i have now are as low noise and speed steady as my direct drive; and both are even heavier. all three have high mass platters and plinths.
Thank you all for your links, explanations, and experiences. 
It seems that some of you have already traveled the journey I'm starting on. I've owned belt driven turntables for many years, and over a year ago I added a Garrard 401 idler drive. Last month I added another idler drive, a Garrard 301.
In my system, my belt-drive turntable is more balanced and at this time if I were to own just one turntable it would probably be a belt drive. My idlers are excellent and I really don't have any issues with noises and rumble that are commonly attributed to idlers. I do feel that my Garrards are better geared towards jazz, blues, vocals, and small ensembles, with this type of music it really shines. With classical and fast music that benefits from an analytical presentation, it doesn't sound quite as good as my belt drive. Perhaps my opinion will change after more work is put into the Garrards, only time will tell.
My curiosity now is how a direct-drive sound, will it sound more like my belt drive or more like my idlers?
your first reaction to a good direct drive is that it will sound somewhat digital, in that it won’t have any character of it’s own. of course, it can sound perfectly natural yet the lack of coloration will require an adjustment. it will have more slam, but not quite the drive, of your idlers. lower noise, blacker backgrounds, wider stage, a bigger, spacious type sound, not quite as focused. it might be more speed steady than your belt drive.

Rock music will soar with direct drive. large scale will hold together. maybe slightly less sexy than the belt drives, maybe a touch less liquid. the contrast will depend on the quality of your three choices for drive types and their level of condition and set-up and ancillary gear.

as you go up the food chain for each of these drive types they all get very quiet and there are fewer downsides of their drive types, just attributes to enjoy. better bearings, heavier platters, higher mass plinths, better motors....matter in each drive type. no replacement for displacement. music loves to be grounded solidly.
Apologies for going somewhat OT.

@ atmasphere:


A good platter pad will simultaneously damp the platter and silence the vibration in the LP; this has to be done with a platter pad that has the same hardness (durometer) as the vinyl. In that way energy from the LP is absorbed and not reflected back the the LP.

I must confess that I don’t really get this, as I don’t see how a mat can simultaneously be an effective and non-reflective absorber of energy and have the same hardness as the vinyl record.

Is there some science available on this subject that I can read? If so, links would be much appreciated.
Mike, you brought up an interesting point...better bearings. IME, this is actually what matters more than the drive type. I think this attribute is one of the most overlooked aspects of turntable design, and yet I think it is one of the most important factors to great SQ!
I replaced the bearing in my 401 idler and the improvement was transformative. So much so, that anyone with an original is not hearing what the table is capable of.
Is the Technics SP10 enough for me to experience many of the qualities direct drive has to offer?

Mike
How are all your new turntables comparing to your reel to reel? I'm on a similar journey with reel to reel as I am with vinyl. 

noromance
link to the bearing you're using would be much appreciated.
At the risk of disagreeing with those who know more,
- agree with the late legend Tom Fletcher, who thought that powerful motors generated powerful vibration hence audible distortion;
- agree with the air bearing crowd who think that all conventional bearings cause vibration in the platter, which is audible;
- agree with the massive platter crowd who think that moment of inertia is the best defence against vibration whatever the source.

My own DIY all-air bearing TT is capable of demonstrating that inaudible noise emanating from the plastic sleeve bearings of its precision 2W motor, has audible effects on the music. Those effects are similar in character to digital, although obviously much reduced. I note that during the launch of the SP-10R, I was allowed to inspect their motor - and I could HEAR bearing noise when turning the spindle by hand. Obviously that matters.

My DIY TT mounts a modified Trans-Fi linear tracker and a higher end Koetsu. Air bearing is the larger New Way thrust bushing running at 63psi.
For me, direct drive. I use the SL1200MK5 (slightly modded by KAB) 
External power supply. Tonearm trough silicon damper, cardas wiring. I am happy.
My TT drive experience is on the lower end of the audiophile spectrum. After many years of non-vinyl listening, I inherited an old, entry level belt drive Hitachi TT. This table was surprisingly good, but I could tell it had some sonic limitations, especially in the lower frequencies. Probably not because it was a belt drive, but because it had a very mediocre tonearm and plinth. I purchased a Project Debut III, NIB, at a significant discount. I upgraded the horrid metal platter to the optional acrylic one. The table was generally very engaging except for the motor noise between cuts and sometimes audible during quiet passages. I also discovered that I am not as hard core as I used to be and hated having a manual TT. I sold the Project and picked up a  30+ year old Technics SLD-303. It is dead quiet, holds speed incredibly well and shuts off at the end. I think the Project sounded better overall because of it's better tonearm and modern plinth, but not because it's belt drive system. I think that I might pick up a more audiophile level second TT, at some point, maybe even a manual. It will probably be a belt drive because the really good DD tables are out of my budget. The summary: At the lower end of the price spectrum, I think choosing the drive system is secondary to the quality of the plinth, tonearm and noise isolation.
Found this video tour of the Thrax factory in Bulgaria that manufactures the Dohmann Helix turntable (the TT of the rich!).  Quite impressive and thought you might find interesting:

https://youtu.be/5QYu6qRg_PA
"I note that during the launch of the SP-10R, I was allowed to inspect their motor - and I could HEAR bearing noise when turning the spindle by hand. Obviously that matters."

Wow, you have sensitive ears.  LOL
I have a belt drive turntable and I can say from MY experience that my direct drive seems a bit quieter to me. Never thought I would say that.
Is the Technics SP10 enough for me to experience many of the qualities direct drive has to offer?

Mike
How are all your new turntables comparing to your reel to reel? I’m on a similar journey with reel to reel as I am with vinyl.

@scar972

there are three different SP-10’s. the Mk2, Mk3 and new R.

and the MK3 and new ’R’ are 2 of the better direct drive choices. they can be very very good with the proper plinth. the MK3 also benefits from power supply upgrades.

i owned a Mk2 and a Mk3, both with Dobbins plinths, back in 2009-2011 and enjoyed them both

assuming you are referring to a Mk2; a step down from those other 2......but.....yes, if it is in good condition with a good quality high mass plinth then it should be able to display the positive aspects of direct drive. it is a great bang for the buck choice. the SP-10 Mk2 can be low noise and explosive sounding and a good one likely betters most under $10k new turntables i’ve heard overall.

as far as RTR and my turntables; the very best tapes are still better.......especially the 1/2", 15ips.; but my vinyl can now be equal or better than many of my tapes that use to be superior. the gap has closed to some degree. these days i am very selective about adding any tape due to this issue.
I’m wondering how can you say anything about "sound" of the drive itself if you can’t put this different type of drives in the same turntable ?

Most likely you’re comparing completely different turntable, no only with different drive system and plinth, but also with different tonearms, platter, armboards and cartridges.

I know only one modern turntable with two optional drive system inside it (Friction or belt, two direct current DC motors) user can switch between them, this turntable is Reed 3C . And when you can change the drive in the SAME turntable then you can say which one is better for your ears.

WATCH THIS VIDEO

But how can you say which drive is beter if your turntables are different (not only the drive is different) ?

You can say which turntable you like, but not the drive alone. Because same drive system can be awful on another turntable.

@scar972 If you want both optional drive in one turntable buy Reed and decide what you like, this will be a fair comparison, the rest is just speculation.

P.S. I'm happy with top quality Japanese vintage Direct Drive like Denon DP-80, Luxman PD-444, Technics SP-10mkII, Victor TT-101 ... and i want to assure they are all amazing. Motor vibration or bearing noise ... it is all myth and fear coming from belt drive users. 


@tzh21y

"Wow, you have sensitive ears. LOL"

The motor was naked for display purposes, and I held it next to my ear. The 2W precision motor was silent in the same test.
@chakster 

"Motor vibration or bearing noise ... it is all myth and fear coming from belt drive users."

No, it is demonstrable.

I have owned all three drive types, and am of the opinion that the DD tables such as the Denon DP 75 and 80 are an excellent value. I suspect the two part platter isolates the record and cartridge interface from the effects of motor vibration that has a direct pathway in many DD table designs. 

Now my personal tables are a Sota Cosmos Eclipse and a Well Tempered Reference, both belt drives of course. Both sound excellent, and offer quality sound. The Sota with the Phoenix Engineering speed control devices has solid sped stability, and even the WTR has no significant speed variations to be heard. There are other advantages to each design that seem to outweigh any limitations to drive design. 

I had divested myself of the Japanese legcy direct drive tables in my system. However, I could not be helped, and I bought a Brinkmann Bardo DD table. It does not use the high torque design of the Japanese tables, and the platter mass is in the 20 pound range. Start up times is similar to a belt drive table, and torque is noticeably lower. However this is a wonderful sounding table. I use an Audiomods Series 6 arm on it with a Ortofon A90, and this table is the most evenly balanced table I have heard. It sounds eerily similar to the Sota, with perhaps a bit more sharpness on the corners of notes. Yes it is like good CD or good tape in presentation. 

All drive formats have the ability to deliver excellent sound. Listen to them, and pick the ones that speak to your heart. 
@terry9

@chakster

"Motor vibration or bearing noise ... it is all myth and fear coming from belt drive users."

No, it is demonstrable.

Please recall some of the best DD with such problem and describe us how can you hear it ?

I think i tried about 10 different Japanese DD turntables and i am not aware of this problem, i can’t hear it when i’m using nice DDs, i use thick Micro Seiki CU-180 and CU-500 gunmetal mats or at least SAEC SS-300 mats on all my direct drive turntables. Also a platter itself is very heavy on DD turntables like Technics SP-10mkII and Luxman PD-444. As neonknight mentioned above a lightweight platters like on Denon DP-80 are special (two layers) so also no problem. And Victor TT-101 platter is also lightweight, but no audible noise or vibrations coming from the motor.

Normally if i can’t detect (or can’t hear) a problem it does not exist for me. My cartridges are not sensitive for some reason, no matte LOMC or MM/MI.

I can’t blame any of my DD turntables using them with the best tonearms and cartridges (many of them).

Belt drive owners should stop scarring people, Direct Drive is an excellent choice today, especially top vintage Direct Drive turntables or brand new coreless Technics DDs.
mikelavigne

... execution is way more significant in ultimate turntable drive satisfaction than dogma...
I think this is true of turntables in particular and just about everything in audio in general. The notion that one technology or design approach is inherently superior to others is misguided because it ignores countless other variables.
If the Brinkmann has a 20-lb platter, that would make it a heavyweight among direct-drive turntables.  Only the SP10 Mk3 and probably the SP10R platters would be similar in weight.  Therefore, the Brinkmann must have a relatively powerful motor, as well.  Since I know it is a coreless motor, that makes it even more appealing.  In my experience, I have come to favor slightly coreless motors (e.g., in my Kenwood L07D and my Victor TT101) vs iron core motors, even though on the other hand the SP10 Mk3 in my 80-lb plinth is the most neutral.  The Kenwood is wonderfully "musical" compared to any others.
On the notion of motor noise in direct drive, there is an ocean of ignorance.  If you hear noise, it is bearing noise, the turntable's bearing.  All turntables have such spindle bearings.  So you cannot attribute that sort of noise as a bugaboo of direct drive.  In essence, a DD motor cannot generate any noise except spindle bearing noise, because the moving parts (the rotor) make no physical contact with any stationary parts (the stator).  Moreover, the motor rotates at a snail's pace compared to the motor of a belt-drive, where the drive spindle is rotating at a much much faster rate.  DD motors CAN generate electrical noise, e.g., EMI.  They generally rely upon the platter and some shielding of the motor casing to prevent EMI from affecting the cartridge.  I do believe the SP10 Mk2, at least my two samples, generated some EMI which did affect playback, faintly.  The Denon DP80 is quieter which is why I've kept it over the Mk2.  And I really do not believe that the SP10R motor made an audible noise, unless it had been abused by hundreds of show-goers prior to being played with.  Which is possible.
Rock music will soar with direct drive.
@mikelavigne  Just FWIW, its not possible to build any sort of audio playback that favors a certain musical genre.
I must confess that I don’t really get this, as I don’t see how a mat can simultaneously be an effective and non-reflective absorber of energy and have the same hardness as the vinyl record.
If you are transferring vibration, to absorb that vibration at all frequencies the material to which the vibration is moving to has to be the same hardness as that which imparts it. In this way all the molecules move together. But at the same time, there is no material whatsoever that can receive vibration and not absorb some of it. This is easy enough to google, here's an example:
https://www.quora.com/What-is-best-known-material-that-can-transmit-vibrations-without-absorbing-vib...


So the trick to to create a platter pad that at its surface has the same durometer as vinyl, but internally is better prepared to absorb vibration- so this does not mean that the material is amorphous. Dissimilar materials are well-known to absorb vibration from each other (we use this principle to damp our preamp chassis, but of course any extensional damping compound is doing exactly that) so a platter pad composed in this manner would be quite effective.
At the risk of disagreeing with those who know more,
- agree with the late legend Tom Fletcher, who thought that powerful motors generated powerful vibration hence audible distortion;
- agree with the air bearing crowd who think that all conventional bearings cause vibration in the platter, which is audible;
If the motor has good bearings and the design of the 'table is correct, any vibration the motor has is quite minimal. To give you an idea of this, the motor in my mastering lathe makes 1/8hp but because the shafts which run between the motor and transmission have isomeric isolation, vibration from the motor is not picked up during the mastering process. The same thing can be done in playback; the motor for the Empire machines is isomerically mounted and simply makes no noise in playback; on top of that the Pabst motor used is notoriously silent despite its amazing amount of torque. Tom simply made too broad a generalization!

Air bearings of any sort provide a different problem! For a turntable to work properly **without coloration**, there must be no play between the platter and the plinth and the plinth must be completely dead while rigidly coupled to the base of the arm; in this way the arm and surface of the platter are only able to vibrate in exactly the same plane. The pickup is thus unable to interpret vibration as a coloration or noise of any sort. To this end of course there can be no play in the bearings of the arm and the arm tube must not be able to 'talk back' (resonant) to any vibration being picked up by the stylus; in essence the cartridge is held rigidly in locus. Air bearings of course violate this basic engineering principle. To understand this better, think about the steering of a car because its exactly the same mechanical engineering principle. The wheel has to stay on the road but has to be guided by the driver. If there is play in this scheme, the car will be dangerous to drive and quite scary. Imagine installing an air bearing in the linkage of the steering of a car!



All have their strengths. My thoughts are to pick the turntable you like.
When naming DD turntables with 20-lb platters and heavier, I neglected to include Mike's NVS and probably the Rockport Sirius, but I can no longer recall whether the Rockport was DD.  Also, any of Dobbins' variations on the SP10 Mk3 theme.  There may be others of course.
I'll try again, since I'd be very interested to find out about this.

@ atmasphere:

A good platter pad will simultaneously damp the platter and silence the vibration in the LP; this has to be done with a platter pad that has the same hardness (durometer) as the vinyl. In that way energy from the LP is absorbed and not reflected back the the LP.

I must confess that I don’t really get this, as I don’t see how a mat can simultaneously be an effective and non-reflective absorber of energy and have the same hardness as the vinyl record.

Is there some science available on this subject that I can read? If so, links would be much appreciated.

the SP-10 Mk3 likely has a platter heavier than 20 pounds, maybe 30, the NVS has a 40 pound platter, the Rockport Sirius III has a 55 pound platter.

as far as Ralph’s points;

absolutely my direct drives did rock in my room exceedingly well.

in order of performance----SP-10 Mk2 < Mk3 < NVS < Rockport.

I am specifically referring to large scale rock, meant to be played a warp 9. direct drive separates parts of the soundstage more effectively than idler or belts, scales larger, and has more slam. direct drives relative weak points......sexiness and tonal density.....are less significant with large scale rock.

all air bearings are not created equal. painting with a broad brush is just not informed. there are general characteristics I do agree. but exceptions too.

same thing with platter pads. every platter is a different case, and different tt weights matter too. no broad brush there either.

“Sexiness and tonality”. That’s what cordless motor driven DDs do better than iron core types, in my experience.
I'll try again, since I'd be very interested to find out about this.
I did respond to this, in my post just prior to this.
@chakster 

To demonstrate bearing noise, I listen to a revealing passage as per normal. Then I turn off the power. No change (other than the obvious slowing of the platter).

Then I remove the drive belt. Change for the better - trace of high frequency tizz disappears. That change is a fraction of the difference between good SACD and vinyl.

Equipment: DIY air bearing table with 45kg platter, linear tracker, Koetsu.
Air bearing stabilizes the platter in 3 dimensions - there is no intrinsic  bearing noise. 
all air bearings are not created equal. painting with a broad brush is just not informed. there are general characteristics I do agree. but exceptions too.
More correctly, painting with a broad brush is not so much 'not informed' as it is less likely to be completely accurate.

I would be interested in hearing about an air bearing that has less play than a high quality bearing of conventional design.
at OP
Scar972 -

the three way table comparison is a fun rabbit hole, and in the link I posted earlier of findings years ago, took my mind off of things during a difficult time. Based on current events - go for it !

Only I would strongly recommend as I showed in my link that I kept the same tonearm, cartridge and wiring on all three tables. My comments were based on this. Who else has done this ?

**************************************

Atmasphere
To understand this better, think about the steering of a car because its exactly the same mechanical engineering principle. The wheel has to stay on the road but has to be guided by the driver. If there is play in this scheme, the car will be dangerous to drive and quite scary. Imagine installing an air bearing in the linkage of the steering of a car!



Funny ! thanks for the Friday laugh Atmasphere.

I would be interested in hearing about an air bearing that has less play than a high quality bearing of conventional design.


The ET2 with its large surface "stationary" bearing is more rigid at audio frequencies than any metal bearings. Bruce Thigpen has done the analysis , documented it - not what this thread is about. I also own high quality conventional tonearms. See my virtual system.

Cheers and everyone have a safe indoor weekend.

The ET2 with its large surface "stationary" bearing is more rigid at audio frequencies than any metal bearings. Bruce Thigpen has done the analysis , documented it
I doubt this very much, on account of one of the metal bearings suppliers in the US requires a security clearance to obtain their bearings (several grades harder than commercially available bearings so they are used in aerospace applications). Now if you can tell me that Bruce has that security clearance (as apparently Triplanar does) then I'm more likely to give this some credence.
I would be interested in hearing about an air bearing that has less play than a high quality bearing of conventional design.

with air bearings there are high pressure, high flow......and low pressure low flow....designs. the high pressure (the Rockport and almost all others) is logically a more robust amount of air pressure building up between metal parts. locations of venturie’s also matters especially for the arm tubes. platter air bearings sometimes are fully captured and other times use an ’air’ film to reduce resonance.

as far as ’less play’ than a conventional bearing i’d say that i’m not concerned about the technical side of what is ’play’.....more about what my ears tell me. and isolating final performance to individual pieces is really guessing for end users.

my low flow-low pressure air bearing CS Port LFT1 turntable and linear tracker give me more detail than any conventional bearing turntable and conventional bearing tonearm i have heard. the bass is otherworldly. magnificent.

https://www.csport.audio/products/products-lft1-en.html
I had run various belt drive tables for years but got the urge to try something different when I listened to a friends Artisan Fidelity Garrard 301. It had an addictive quality that the TW Raven AC sitting next to it did not seem to capture. So I set about looking for a modern idler-type table after exploring various restored vintage tables and the PTP Lenco. I decided I wanted to see if someone would achieve better results by bringing modern technology to an old design concept. After nearly a year wait and lots of helpful and informative communication back and forth last week I received a Sempersonus TE-2, the first to arrive here in the US. You can learn more here: https//sempersonus.com/te2-our-first-turntable/

I worked with Jeffrey Catalano at High Water Sound NYC on a TW Raven (12 Inch) tonearm and a Charisma Audio Signature One cartridge. I'll come back and post some comments about the sound on another thread but just thought I'd share as the table uses an "epicyclic drive" system that is essentially and inner rim drive with an electronically regulated speed control system. The table is beautiful to look at and a breeze to set up. If anyone is interested I've got pics posted on my virtual system. 
my low flow-low pressure air bearing CS Port LFT1 turntable and linear tracker give me more detail than any conventional bearing turntable and conventional bearing tonearm i have heard. the bass is otherworldly. magnificent.
If you didn't use the exact same platter pad, cartridge and arm on both machines, this might only be anecdotal wrt the platter bearing type.
New Way air bearings have amorphous carbon faces, resulting in literally millions of ’apertures’. I saw a U-Tube presentation of a shaft rotating in an air bearing (maybe New Way), spinning freely, when the high pressure air supply to the spindle was cut. The shaft came to an abrupt stop with a bang - it was immovable. Now that’s low tolerance!