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I tried in other forums but no one seems to be interested in such topic so I will try it here.
Having seen so many so called high end turntables that a majority of them do not separate or decouple the bearing shaft from the spindle. I strongly believe separating the record spindle from the bearing can reduce noise significantly. At an audio shows I encounter a turntable designer and he agreed with me and said it is understandable in manufacturing budget turntables to reduce the cost. But when it comes to high price turntable exceeding $10K there's really no excuse.
Turntable with sub-platter should not be that hard to have a top platter with a separate spindle. Many small companies are founded by machinists who are not designers themselves and just keep doing the same thing over and over with added blinks to the appearance to justify the high cost. I keep seeing thicker and thicker platter and yet the bearing shaft still protrudes all the way up to be the spindle. Make no sense to me...
At least some designers pay attention to this issue. In a Stereophile interview, Spiral Groove designer Allen Perkin, formerly Immedia, said this: "People assume that a lack of friction means a lack of noise, but I've found that most noise comes through the spindle. The part of our spindle that touches the record isn't even part of the bearing, which makes machining quite difficult."
In another interview has this introduction: "he believes that his platter bearing is very different from those used in other turntables in that the spindle and platter bearing are decoupled yet precisely aligned."
Even if the precision of the alignment can be an issue, the tolerance of eccentric record is still greater than that!
I have seen some examples like GrooveTracer subplatter using a decoupled spindle. But the spindle is still touching the bearing shaft though. I would prefer it to be completely detached from the bearing and to be part of the platter. But I understand it's sold as a Rega accessory so it has to be user friendly to existing Rega users.
Another concern is the use popular use of inverted bearing that the thrust pad distance is very close to the record surface compare to the conventional "stick in a hole" approach.
By the way, we are talking about bearing and bearing only. I am not implying all the other things such as tonearm, plinth, suspension, etc... are not important. I am not talking about those things, only bearing design and its interaction with the platter and record. When you design or build a bearing for a turntable, these things do come to mind.
I have experience with noise before when a record clamp is used, hence my question.
Again, I am mainly talking about high end or expensive turntables not the type that has limited budget.
Any thoughts?
Follow Ups:
I do not and yet it seems to me after reading through all the posts no one had addressed how does noise/vibration travel through various materials and does it want to take the shortest route.
If the shortest route was reality then the cartridge should pick up the most noise closest to the spindle. ( In reverence to bearing noise)
It would be great if someone could explain how vibration travels and can be redirected or dissipated. It seems like a stretch to think alot of noise is coming straight up the spindle across the surface of the record to the cartridge.
Enjoy the ride
Tom
TomWh: "It seems like a stretch to think alot of noise is coming straight up the spindle across the surface of the record to the cartridge."
I can only speak from experience. I used to own some Empire 208 turntables and they use a steel bearing for male and female parts. They are quite noisy and, with oil, I can even hear the scraping sound when I hold it close to my ear. The same thing with some Rek-O-Kut tables, another one that uses steel on steel bearing. I can hear it in the music background in soft passages. The noise is lessened when I use thicker oil. I took out the 45 adapter and stuff that area with blue putty and is quieter. My friend used a huge wad of blue putty around the casing of the bearing and reported silent result. The kind of bearing with bronze sleeve is much quieter but they don't last as long as steel of course. You gain some you lose some. Bearing noise is real. You might think it's groove noise but you know it when the bearing noise is gone. Other than the motor, it is the noisiest part of a turntable because it moves with metal to metal contact. Of course, it's possible that some tables up to certain price point might have quality bearing that makes bearing noise inaudible. YMMV.
Regardless of the physical linkage or lack thereof, of the bearing to the spindle, the spindle has to be the center of rotation of the platter. So, how would you effectively decouple the spindle from the bearing, in a world where gravity is "the law"? One practical method that has been used in the past is to magnetically levitate the vertical bearing, in which case the spindle and bearing are still not isolated from one another. Instead, the upper bearing surface is isolated from the thrust pad. My point is that if you are worried about transmission of noise from the bearing surfaces to the spindle and hence to the platter and LP, there are "solutions" extant that do not require separating or isolating the bearing from the spindle. Other than maglev, what do you suggest? I agree with Tre' that for other reasons it is best to have firm linkage from LP to tonearm.
Lew: "So, how would you effectively decouple the spindle from the bearing, in a world where gravity is "the law"?"Make the spindle part of the platter but not the bearing shaft? The kind that has a sub-platter is rather easy. For example, look at the video below of the Bergmann turntable. I hope it illustrates my point.
That also brings me to an observation about Lenco users adding another platter on top reported positive result is partly because of the decoupling of the spindle from the bearing. Similarly some German users like adding an acrylic platter on top of a Micro-Seiki turtable may have similar benefit.
=============================================Lew: "Other than maglev, what do you suggest?"
Mag-lev is a good way to lessen the mass of the platter (Continuum does that) but I think most still have the bearing bottom end touching the thrust pad instead of floating that might affect VTA. I saw a video of a Clearaudio mag-lev bearing that the platter can be pushed down and spring back up when released. Not sure if that's vertically stable when playing a record. It might. I don't know.
Airbearing is completely isolated. Whether that thin layer of air is rigid enough to not have vertical movement is up for debate. I'll leave that to the airbearing experts.
Edits: 10/24/16 10/24/16
Here are two examples of after-market modifications that seem to aim at the same thing as that Bergmann platter:
http://www.arche-headshell.de/accessoires/sdp-the-sonically-most-effective-upgrade-for-every-turntable/
http://tinypic.com/view.php?pic=10ge1pt&s=8
Plato65: "Here are two examples of after-market modifications that seem to aim at the same thing as that Bergmann platter":
SDP platter mod & Garrard 401 platter mod
Thanks for the examples. That German website is what I was talking about in my reply to Lew.
Several other turntables over the last few decades have mounted the platter on top of a smaller subplatter that is part of the spindle and bearing. (Now that I see the video, I understand better what you were talking about.) I think my old Thorens TD125 was like that, and there are more that I cannot name off hand, maybe including the original AR XA. If one were inclined to pick nits,one could say that since the actual platter has a large physical contact area with the carrier subplatter, spurious energy could easily be transmitted into it from the subplatter, using the method you seem to admire. The SP10 Mk2 bolts the "top platter" (in your parlance) to a smaller carrier, using 3 machine screws. This is good for structural stability but further enhances energy transfer, if one is terribly worried about that. On the maglev side, you are neglecting the Verdier, where the vertical suspension is entirely magnetic, and the massive magnets mostly interdict unwanted up or down motion of the platter that could effect VTA. Some love the Verdier, some do not. IMO, in a belt-drive, there is more issue with motor vibration being transferred into the platter via the belt, vs energy from the bearing friction.
Lew: " I think my old Thorens TD125 was like that..."The 125 (or 160 or Linn LP12 for that matter) uses a subplatter but the top platter has a huge hole that allows the subplatter to be part of the whole surface where the record touches so the spindle is still a part of the bearing shaft. I owned one before so I remember its construction.So it's not the genre I have in mind.
Here's an inverted bearing as an example that I question about noise... Notice how close the thrust pad is to the record...
Edits: 10/24/16
My Rockport Capella II with standard ruby bearing has a flat top (no spindle) sub-platter, which the main platter with its spindle sits on. However, since the main platter is connected to the sub-platter metal to metal with 6 bolts , I can't imagine this arrangement has any effect on decoupling the bearing noise!
Caligari, I've always felt that coupling was a product of overlapping area. A spindle barely offers much at all perhaps just one point of contact unless the LP hole is really tight (in which case it should be reamed anyway ;^)For example, reducing it by using multi-tiered supports which are spiked onto each successive level(?)
Continuing this chain of (possibly flawed) logic, it's reasonable to expect that the entire platter, not just spindle, will be detecting and transmitting vibration/interference from motor/s and other sources. As mentioned earlier the overlapping area of LP-to-platter is normally far greater than the contact area at the spindle. So my goal has always been to minimise that coupling too (i.e. so-called "undamped" approach to LP replay).
I do this by using mats which reduce contact area between LP & platter but which give more than enough friction to drive it. Needless to say the method also involves avoidance of clamps or weights.To give examples there are the Ringmat (which I prefer) and the Trans-Fi "Reso-Mat" which I also own but do not prefer because perhaps it doesn't "mechanically ground" the LP quite enough.
This is not to say that other (damped) approaches such as JE's, properly implemented, do not work admirably, because there are many alternatives that I admire.
Hope this helps.
Edits: 10/24/16
John Ellison- After all, the bearing is spinning at only 33-1/3-rpm and can be made to operate basically noise free.
Caligari- Seriously, what really bothers me is that these so called "high end" or perfectionist manufactures keep talking about attention to details and yet (leaving the motor out of this equation for now) they don't address the source of the noise, the bearing that is a moving part!
I include part of the above, as I have thought and had read in other posts that the bearing and shaft are not moving/spinning but remain stationary- the platter is spinning on the stationary bearing. My VPI Super Scoutmaster bearing, for example, is fixed securely to the spindle and the bearing spindle is bolted to the plinth.
> My VPI Super Scoutmaster bearing, for example, is fixed securely to the spindle and the bearing spindle is bolted to the plinth.
Are you suggesting that the platter spindle on your VPI Super Scoutmaster bearing does not spin with the platter? I can't imagine that VPI would design their turntables like that!
What you are describing is called an inverted bearing when the bearing shaft is bolted to the plinth and the bushing and thrust-plate are connected to the spinning platter. My Sota Millennia is designed this way but its spindle is connected to the spinning part of its bearing and spins with the platter.
I think the spindles on VPI turntables are also connected to the spinning part of the bearing so they spin with the platter. Am I wrong? Does the spindle on your VPI actually remain stationary as the platter spins? I can't imagine that would be good! On the contrary, I think it would generate noise as the record turned against a stationary spindle. My Sota Millennia is definitely not designed like that. It's spindle is connected directly to its platter and spins with the platter.
Best regards,
John Elison
John, Yes, the bearing shaft/spindle is bolted directly to the plinth, and the ball bearing is press-fitted into the end of the shaft, where the platter then goes over it. The shaft and bearing are stationary. Harry made a special oil-pumping feature for me in the platter for the inverted bearing. The entire operation is very quiet with black background. The platter is controlled by rim-drive off the HRX double motor and sounds great with the 3D arm and Lyra Titan-i cartridge. I also use the Phoenix Engineering Eagle and RoadRunner.
...but not always realistic. Consider the noise inherent on most, perhaps all, LP's. As I got quieter and quieter turntables culminating in my VPI/Denon DP-75 rig, it became easier to distinguish mechanical and electrical noise actually pressed in the LP. There's a floor somewhere, where the medium becomes the limiting factor.To sink beneath that floor is unproductive and takes you past the point of diminishing returns. The mechanical design improvements you suggest are likely very costly to implement and would improve noise in the Nth decimal place. They in effect become another gimmick.
Being the engineer for a small production shop (sculptural fabrication, not turntables) I don't necessarily feel that "companies are founded by machinists who are not designers themselves and just keep doing the same thing over and over with added blinks to the appearance to justify the high cost." Owch! Well, perhaps for some clients yes. We constantly seek out higher grade designs, materials, and processes to remain competitive. But our best and wisest decisions are based on spending the money where it provides the finest overall finished product.
I do concur with you to the extent that the dearth of design money and talent in phonography today lies at the root of this problem. As an example, to design and tool up for an all-new, superior DD turntable or an all-new SLR film camera would cost perhaps $1MM and take a year. No manufacturer will commit to that so they just keep adding more belts and motors to the basic belt-drive claiming its "new." I assume the manufacturer's are waiting for the wave of interest in LP playback to pass, when this Bear is a rug...
Edits: 10/23/16 10/23/16
Thank you for your comment. Do you recommend using record clamps in this case?
There have been scores of discussions through years regarding clamps and weights. I don't make it a ritual, but I do have a clamp with a chuck with a fine thread that draws it down as tightly as wanted. I almost always use it, at least clamped very lightly. Too tight and it can make the record cup-warp. That's in part why I wouldn't use a weight. I don't like added load on the bearing either.
A clamp seems essential for records with enlarged holes, as a minimum.
The theoretical notion of coupling the disc to the platter mat is a good one, however it seems some discs sound a little sweeter with no clamp. Like many structural-dynamic issues, results are counterintuitive.
Think in terms of "IF", whenever possible. "IF" the one-piece bearing shaft/spindle structure is designed well, it will perform it's work silently enough. "IF" a two-piece bearing shaft/spindle structure is designed well, it too will perform it's work silently enough.
That said, I think John's idea makes the most sense. Because of the risk of "discontinuities" leading to unwanted reflections (poor impedance matching), I think it could be harder to design a good two-piece structure than a good one-piece structure.
Perhaps the question to ask is with a precision machined bearing setup, is there enough "noise" to be audible? A cartridge is a transducer, not a microphone, so the only way it can transmit an electrical signal is when its' magnetic field is altered by means of stylus/cantilever movement. So in this case, "noise" can only manifest itself as the result of vibration (assuming the LP itself isn't moving around), and I question whether there is enough vibration caused by any higher-end turntable bearing to even be audible. I would think vibrations external to the bearing (structural, airborne, etc) would have a much more significant impact than whatever vibration comes from the bearing, especially with the miniscule contact area between the records center hole and the spindle.
Just my $0.02...
are of very simple construction...They have a ball or ball shaped shaft end that rotates on a thrust plate. The contact area will be polished but anything mechanical will have irregularities. These will displace the whole spindle platter assembly and introduce noise. The rotating element has to ride up on the bumps between the two surfaces and then drop down into the valleys. That will definitely cause some displacement of the stylus in the vertical direction. Any wobble of the bearing will create stylus displacement mostly horizontally. Either can be measured as a noise signal on the cartridge. Bearing noise is a fact.dee
;-D
True terror is to wake up one morning and discover that your high school class is running the country.
quote by Kurt Vonnegut
Edits: 10/23/16
Penguin,
No argument that a bearing (any bearing) will create noise when it is turned. What I question is whether that noise will be audible in a higher-end 'table given the typical machining quality, and further, whether the small contact area between the LP and the spindle will transfer any appreciable amount of whatever noise is there through a compliant medium like vinyl. I'm not making a proclamation here, just voicing my thoughts based on a number of different 'tables I've owned.
My Sp-10 MK 2 is rated for 73 dB SN. that is very quiet by any standards. But some of the noise is still mechanical, some is electronics. User510 had a bunch of measurements with different bearing materials, and there were differences :).
dee
;-D
True terror is to wake up one morning and discover that your high school class is running the country.
quote by Kurt Vonnegut
Does tonearm resonance amplify the bearing noise? At what frequency does groove noise appear?
Found this one done by Thorens
Ask the question...Does it matter?. Say groove noise is at -60db, the total noise of the table is -72db....what is the cumulative noise? i would venture to day that it is not more than -59.9 db, a minute addition form the the low level noise of the table itself. Since both bearing and grove noise is caused by friction, they would have similar character, as opposed to noise from EM fields of sorts. If you look at User510's measurements you see more of an amplitude change in certain spectra as opposed to the shift of the entire spectrum. Think about it this way. A piece of sandpaper will make different scratching sound on wood, steel, glass etc. but will you hear that on a train with the windows open?
dee
;-D
True terror is to wake up one morning and discover that your high school class is running the country.
quote by Kurt Vonnegut
You're right it doesn't matter. Noise is noise. I was curious. just wanting to identify what I see.
With my arm and cartridge, the tonearm resonance should be about 10 hz. I guess the bearing noise is in the same area. Groove noise?? spread over a wider part of the spectrum?
Recorded from AP test record silent groove, 64 db gain setting on Sutherland.
Since I record all of my LPs, I can fix it with a high pass filter at 20 hz. Then it looks like this.
I think modern platter bearings can be made almost noise free. I have a feeling the "rumble" we used to hear about was caused more by the motor than the platter bearing. Idler drive turntables were probably most susceptible to rumble from the motor. One of the reasons for belt drive platters was to minimize motor noise from affecting the platter. Direct-drive turntables seem to have very low rumble measurements, too.
This is just my opinion. I haven't made any measurements, but I don't think platter bearing noise is anything to worry about on either of my two turntables.
Best regards,
John Elison
You seem to be implying in your diatribe of a question that we all know the answer yet nobody is willing to discuss the matter with you. It might just be that nobody knows the answer and/or nobody really cares. I'm kind of on the side of not caring because I'm perfectly happy with the design of my platter/bearing/spindle.
If I did care about it, I believe it's better to have the spindle and bearing machined as a single piece because I believe it will absorb and damp unwanted vibrations better and thereby produce lower overall noise. Anytime you have a discontinuity, vibrations tend to be reflected at the boundary instead of being absorbed and damped. Modern high-tolerance platter bearings will absorb and damp vibrations generated by the stylus tracing the groove while introducing negligible noise of their own into the system. After all, the bearing is spinning at only 33-1/3-rpm and can be made to operate basically noise free.
Anyway, that's my opinion on the subject and that's why I use a spindle clamp on a turntable having vacuum suction to hold the LP tightly against the platter. To each his own!
John Ellison: "If I did care about it, I believe it's better to have the spindle and bearing machined as a single piece because I believe it will absorb and damp unwanted vibrations better and thereby produce lower overall noise."
So tightly coupled to the source of noise will lower noise floor? Give me a break.
You certainly don't care but you just can't resist posting picture of your turntable for the umpteenth time!
I don't believe the platter bearing is a source of noise in modern turntables. At any rate, my Sota Millennia is the quietest turntable I've ever heard in terms of groove noise and music emanating from a black background. On the other hand, if you've never heard a low noise turntable I can understand discontent, but I guarantee it has nothing to do with the spindle and bearing being made in one piece.
You asked a question, but it's obvious you didn't really want to hear any answers that you don't agree with. That's why I called your question a diatribe. I realized your purpose immediately. You simply wanted to criticize all turntable manufacturers that didn't build their platter bearings to your specifications because you think you know more than anyone else. The fact of the matter is you're very ignorant.
Your ignorance is further demonstrated by objecting to pictures of turntables in the vinyl asylum. That's laughable! People post pictures of their turntables all the time. If you don't like my turntable, don't look at it.
As I stated earlier: "To each his own!" Apparently, you don't get that, either. Such is life!
Good luck,
John Elison
By the way, you're the one who used the word "diatribe" first before giving your reasoning so please spare me the lecture.To be fair, I never owned any table of the quality and expense of yours. Maybe it doesn't matter once it reaches that price point. So in that, you have a point! That also acquits me of having an agenda or pretending to know more than other turntable makers. I simply asked a question.
Edits: 10/23/16 10/23/16
I think the answer to your question is this, the chain from the stylus to the record to the platter to the platter bearing through the chassis to the arm board to the arm base and through the arm bearings to the arm tube to the head shell to the cartridge..... needs to be as tight and free from play as possible.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Here's the perfect turntable for you. Neither the spindle or the platter connect to the bearing and it's well within your price range. ;-)
Haha! Good one!
I saw that one before. Good luck to them getting that one funded!
It would be fun to adjust the floating height for VTA. :-D
Hi
Roksan have an interesting take on this: since its introduction, their Xerxes deck has featured a detachable spindle. You remove it once the LP has been guided into place, so there is no longer any contact with the platter or bearing except via the mat.
I think the only Roksan model that doesn't feature this is the entry-level Radius.
HTH
Mark
I have a Roksan Xerxes and can say, for me, the only effect of removing the detachable spindle is that you will inevitably lose it ... and when you do you will enjoy the experience to paying some ridiculous amount for a replacement, which if you're really lucky, will be made out plastic unlike the original metal.
If I understand your question correctly the reason is for concentricity an important factor in itself. Old machinist.
...and smart guy. :-)
REMEMBER our Lps are (or at least were) 5$ recordings.
Most are either Worn or recent Thrift store buys.
How..anal does one needs be ?
When you consider that the hole is rarely in the exact middle of the record, you want to make sure that you don't make bad matters worse.
To the original poster's point, there are many considerations that come into play, and turntable design, like anything else you care to name, has countless nuances. I will agree that there are quite a few careless approaches to spindle/bearing design, however.
mosin: "I will agree that there are quite a few careless approaches to spindle/bearing design, however."
Well said!
just saying, and you know what i mean :)
dee
;-D
True terror is to wake up one morning and discover that your high school class is running the country.
quote by Kurt Vonnegut
Did I ever mention what a great guy you are? ;-)
well thanks....
dee
;-D
True terror is to wake up one morning and discover that your high school class is running the country.
quote by Kurt Vonnegut
Hi Caligari,
I think a simplistic answer to your question would be that, typically, fewer parts means lower costs when manufacturing anything, be that a pair of roller skates or a turntable, low or high end.
Making the bearing shaft and spindle from a monolithic turning is easy to do using very common manufacturing methods. Separating the spindle from the rest of the shaft/bearing body introduces some extra pieces and would require some precision to ensure the centers were concentric and parallel.
That's not impossible, of course, nor super costly, as it's done quite commonly for all manner of mechanical devices.
The next question becomes that of cost/benefit. Hard to say if manufacturers have tried other options and come back to the monolithic approach, that they're able to satisfy market requirements with the monolithic approach and see no need to change, or they just haven't tried.
Maybe you could be the one to advance the leading edge here...
Thank you for your post. That's the type of comment I enjoy reading. I am not a turntable maker but if I am I would implement those ideas.
Seriously, what really bothers me is that these so called "high end" or perfectionist manufactures keep talking about attention to details and yet (leaving the motor out of this equation for now) they don't address the source of the noise, the bearing that is a moving part! They keep adding thickness to the platter and yet that damn spindle is protruding all the way up to be in contact with the record! And as you said, it shouldn't even cost that much but they don't address it and will probably say it's not that important. If I can afford a 6-figure table, I ain't buying one that doesn't address that issue, period.
Thanks again for your comment.
IF so concerned?
Ream out your LP centers and fit a bit of silicone ring/tube as an Isolator so the lp never directly contacts the spindle..
IF the LP has no direct contact to the spindle the Problem(?) is moot.
Edits: 10/23/16
and put a silicon rubber tube over it? On the other hand i do nto think it is a huge source of noise in a high end TT. Maybe there is more to be gained from the mechanical grounding a well designed thrust bearing affords. After all you loose more resolution beating against a spongy bering than a solid one.
dee
;-D
True terror is to wake up one morning and discover that your high school class is running the country.
quote by Kurt Vonnegut
My Xerxes X has a removable plastic (some were aluminum) cap which fits over the spindle. Once the record is on the platter, the cap is removed for play. The pictures above show what it looks like with the cap removed.
I'll be honest, and say the closest I ever got to hearing a difference with or without the spindle cap was a "maybe". And when the best I can do for any change, tweak, wire, etc. is a "maybe", I consider it a "no".
I play my records with the spindle cap in place, and call it good.
'Ow many ha' you reamed like thi'?
bare: "Ream out your LP centers and fit a bit of silicone ring/tube as an Isolator so the lp never directly contacts the spindle..."
Clever. I like the way you think. :)
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