ABEC bearing ratings

[Wakefield Turntables]

I've been looking at another tranch of upgrades for my 1210 and one of the things i'm pondering is to have the bearing upgraded on my SME V. Currently it's got an ABEC 7 rated bearing. Has anyone on AOS got experience of these higher rated bearings especially ABEC 9? your comments would be welcomed.

[Stratmangler]

I've been looking at another tranch of upgrades for my 1210 and one of the things i'm pondering is to have the bearing upgraded on my SME V. Currently it's got an ABEC 7 rated bearing. Has anyone on AOS got experience of these higher rated bearings especially ABEC 9? your comments would be welcomed.

There you go, playing the Audiophile numbers game :rolleyes:

What do SME reckon to changing the bearings?
If they say it will improve things, then do it. If they say it won't improve things then don't do it.
My guess is that SME will tell you politely to go away ;)

[Marco]

Lol - indeed... Andrew, if you must upgrade, you'd be better off buying a better (whole new) tonearm! :eyebrows:

;)

Marco.

[The Grand Wazoo]

Not that I think it matters too much, but I thought the SME V's already had ABEC 9 bearings?

[AAshton]

Not sure how relevant ABEC ratings are for tonearm bearings as the movements of a tonearm are limited in both range and speed compared to the majority of uses of bearings. Always sounds good for the marketing folk though.

Andrew

[Wakefield Turntables]

Hi Andrew,



Lol - indeed... Andrew, if you must upgrade, you'd be better off buying a better (whole new) tonearm! :eyebrows:

;)

Marco.

Marco, I thought you'd say that. Perhaps you could recommend an ortofon tonearm :D


Lol... IMO, more people should shun the boring 'obvious' choices. I have five words of advice: Think Outside Of The Box, for there is where true joy with audio lies!

Some of the (saner) tonearms illustrated on this thread would sonically outperform an SME V, in most cases, either for a similar amount of dosh, or less:

http://theartofsound.net/forum/showthread.php?t=14624

Marco

[Barry]

I was always under the impression that SME thought bearings to ABEC 9 tolerances would not withstand the stesses put on them through handling of the arm.

However, the bearings used in dentist drills are to ABEC 9, and they take a lot of punishment in drilling teeth.

So I don't really know. If I were you Andrew, I'd leave well alone - the SME V is a dammed fine arm as it is. :)

Regards

[DSJR]

It's as Andrew says and more to do with rolling-speed stresses rather than anything else (I understand from a mechanical engineer). FFS leave the SME alone, there's nothing wrong with it at all, even if certain parties here dislike it :lol:

Marco's right though. if you want to change (not necessarily "better") the sound you're getting, either look at a cartridge change, or a different kind of arm - one of the better unipivots perhaps???????

[Audioman]

If you dismantle an SME arm to change the bearings you will certainly F it up. In fact all recent SME arms use a common bearing (ABEC 7 or 9 ?) not as it says on their web site. What type is pretty irrelevant as the worst bearings they may use are more than robust enough. Wiring or cartridge change would be the way to go if you want to tailor the sound.

[Marco]

Hi Andrew,

Apologies - I've edited my reply into your earlier post, rather than quoting it, so have fecked it up - sorry!! :doh:

That's what I get for staying up until silly o'clock this morning listening to music :rolleyes:

Anyway, I think you can get the gist of what I was trying to say :)

Marco.


Hi Andrew,



Lol... IMO, more people should shun the boring 'obvious' choices. I have five words of advice: Think Outside Of The Box, for there is where true joy with audio lies!

Some of the (saner) tonearms illustrated on this thread would sonically outperform an SME V, in most cases, either for a similar amount of dosh, or less:

http://theartofsound.net/forum/showthread.php?t=14624

Marco

[sq225917]

The ABEC rating system does not measure any parameter that would be in any way beneficially improved by going to a higher rated part in a tonearm. You should take the time to read the relevant specification documentation. There is no measurement for stiction in the ABEC spec and that is the one thing that would make a difference in a tonearm as it would effect movement and grounding of vibration.

[Barry]

The following might be of interest:

http://en.wikipedia.org/wiki/ABEC_scale

http://www.nmbtc.com/bearings/abec-bearings.html

http://www.astbearings.com/abec-quieter-bearing.html


The ABEC rating system includes grades 1,3,5,7, and 9. The higher the ABEC rating, the tighter the tolerances are, making the bearing a more precision part.

The dimensions and tolerances controlled by the ABEC standards include the diameters and widths of the raceways, their shapes to some extent and the smoothness (roughness) of the running surfaces. The ABEC rating system ignores, side loading, impact resistance, materials selection and grade, appropriateness of lubrication, ball retainer type, grade of ball, the clearance between the balls and the races, installation requirements, and the need for maintenance and cleaning.

As such, it is a much misunderstood and largely unhelpful grading system.

[Bwaze]

Franc Kuzma on the topic:


Ball Bearings for tonearms
09.01.2012


Ball bearings – the myth of ABEC quality

In the audio press and in advertising it is often mentioned that tonearm manufacturers are using best quality bearings, stating ABEC 7 quality. Does this statement have any practical use?

Let us check what an ABEC standard actually means. It is a US standard for classifying certain parameters of ball bearings. In this case it only guaranties that ball bearings are made to specific sizes and tolerances. The higher the number, the tighter tolerances of the bearing.

In any production process when parts are made, their dimensions have to be specified. It is almost impossible, for example to make a shaft exactly 20.000 mm in diameter. In production tolerances are used, which tell us how much bigger or smaller than the exact 20.000 mm the shaft can be. For example for that shaft to fit a hole of 20 mm in bearing housing, it would need to be smaller. The shaft can be made 0.1 mm smaller or only 0.01mm smaller. The smaller the size variation which is allowed, the tighter is the tolerance and the more difficult to make. The same applies for the hole size. It can be made bigger for 0.1 mm or 0.01 mm. I believe you get the picture.

ABEC standard ( US) or ISO ( European) prescribes only certain basic dimension tolerances of ball bearings. In ball bearings there is an outer and inner ring, balls and a cage which separates the balls. All these parts are made within certain tolerances to fit together and to be built into products.


ABEC and ISO standards do not cover: radial play, surface finish, material, ball complement, number, size or precision level, retainer type, lubrication, torque, cleanliness at assembly, raceway curvature, packaging and other factors that may be essential to the desired bearing performance.

I would like to emphasise a few of the most important parameters which are not covered by ABEC: Starting torque which affects the swinging of the tonearm up and down and following eccentricity of the record, noise level and vibration in bearings which adds distortion, cleanliness of oil which may restrict movements. It will not tell how precisely the ball bearings are fitted into the housing and shaft of the tonearm, which has direct influence on smooth zero play and movement of the tube in all directions and across the whole record playing area.

When you read about the quality of the ball bearings in a tonearms ask yourself ˝Did they choose the right bearings and are they fitted in the best possible way"? Just stating ABEC means the same as declaring that amplifier A is the best because it has the lowest measured distortion and, as we all know, this has nothing to do with good sound itself.

[flapland]

The ABEC rating system does not measure any parameter that would be in any way beneficially improved by going to a higher rated part in a tonearm. You should take the time to read the relevant specification documentation. There is no measurement for stiction in the ABEC spec and that is the one thing that would make a difference in a tonearm as it would effect movement and grounding of vibration.

I know the ceramic bearing used by Jeff Spall who is Audiomods was chosen for its low stiction attributes as much as anything. I would have thought SME as a engineering company at heart would spec and test the bearings for the best quality required to do the job and therefore the V is unlikely to be improved by a change. Perhaps your money better spent sending it for a quick service or elsewhere.

Of course I don't claim to be any kind of expert in this area.

[sq225917]

Low stiction and close tolerance don't go together unfortunately a loose bearing is a loose bearing, you have to place your cards somewhere on the scale. Specifying bearings with the highest level of roundness, grade 5, and the highest level of race polish would be the way to go, add in a race/ball material with the highest Vickers rating and you should have a solution.

That said, it's probably cheaper just to buy a box full of well specced bearing and hand select them.