In general - "skating force" is not linear. It is general with modern styli much less than it used to be in the 1970ies. Several respected tonearm designers (Pierre Lurne, Mortensen, ...) do recommend not using anti-skating at all and for good reason - applying a steady and linear "anti-force" upon a non-linear force is not a good idea at all......
Dampening - if you REALLY need it, the cartridge/tonearm match is less than optimal in terms of its mechanical parameters.
In general - less is more with both issues.
If you apply any dampening fluid, do use as little as possible and do use fluid which is NOT like honey but more like water......
If you apply antiskating at all, do set it as little force as possible - 1/2 of what is recommended by the manual will be enough and more than that.
The higher the VTF - the lower the antiskating ! |
Skating force is a result of the offset of the polished area of the stylus in perspective of the groove wall. During the journey of the tonearm cross the record side this offset becomes zero 2 times - the zero tracking error point - and is depending on the tangential error angle (which changes all the time - becoming more and less again during the journey from and towards a zero error point).
Less derivation from tangential zero error = less skating force.
Skating force too is influenced by misalignment of the stylus in the groove and - to a VERY high degree - by the total contact area. Larger contact area (= modern line contact) is far less force on the groove wall with a given VTF as the skating is a by-result of VTF divided through contact area.
In summary:
- less derivation - offset - from tangential zero = less skating force.
- super precise vertical alignment of stylus in groove = lower skating force.
- larger contact area of stylus = lower skating force.
- old - conical or elliptical - stylus = higher skating force compared to line contact or similar.
MOST IMPORTANT: skating is NOT linear, but a force which gets higher, lower, zero and higher again.
Trying to compensate such a force with a linear anti-force is......... well....... no good idea.
"Correctly applied" anti-skating would fix the problem in 2 short moments of the record side and produce a new problem for most (98%...) of the rest.
Then there still is the (objective and empirical by observation ...) "fact" that most tonearm/cartridge- combo featuring very high VTF (2.5 grams +) do indeed produce LESS skating force .........
Thats why Ortofon did not care for antiskating at all in its 12" tonearms w/SPU cartridges and why my FR-66s runs smoothly w/ FR-7fspec. without any anti-skating....... |
Indeed - God bless america.
Especially so in our troubled times.
Thanks to him, that not all americans always go for the most simple model in everything......
In this sense - good luck to Nsgarch too. |
Nsgarch explanations are based on the original patent description of skating force and the anti-skating applied. And its too is not a matter of MM-cartridges vs MC-cartridges. Their different basic mechanical characters do contribute some details to the behavior, but not essentially so.
This general patent description from over 60 years back - while not entirely incorrect - is an incomplete model and is simplifying a quite complex issue. All anti-skating devices designed for tonearms are based on this patent description and a simplified model which gives the impression that skating is a constant force which can be nulled with a correct applied counterforce.
Well - it is a neither constant nor linear force and it is depending on tonearm length (with the resulting offset being more or less depending on effective length), stylus shape, size (especially so by older elliptical/conical styli, which do create a "double-side-contact" towards the inner grooves! )and alignment, groove cut, VTF, groove-compliant VTA and tonearm geometry aligned for (2nd zero close to inner grooves give another benefit here... see our sadly deleted tonearm geometry thread from early summer...... if you saved it in time).
As I said before - this is NOT a simple model.
I still believe that it is rather smart not trying to counter a highly variable force with a constant applied anti-force. It is obvious, that there are only very few seconds of the 20-35 minutes of a record side in which the counter-force is really correct and nulling the skating force of the moment. During the rest of the time the anti-skating applies a more or less unwanted side force of its own - just going in the opposite direction.
With the standard "skating vs. anti-skating"- model we have a model which is incomplete and the consequences drawn from it were wrong.
We would need a variable anti-skating force based on the tangential curve of the given tonearm. This antiskating force would then be inverse to the tangential curve and would indeed null the skating force if properly aligned.
Several questions in tonearm geometry today are long set aside as "complete", but are based on models which were simplified and as a result of this simplification did not give the correct results.
But so far we are living with these - less than optimal - results.
Partly due to laziness, lack of knowledge, partly ignorance (this is not meant to offend anyone !!), partly ease of use. |
Newton would smile.....
Again Nsgrach - your simplified model does not meet reality.
It is obvious and a simple fact that the skating is altering - ever seen any skating in the zero point ?
The offset is changing - and so is the amount of skating force.
You are calling for simplicity - this is a very simple fact.
Where is your problem ? |
Dear Stan, you are of course right. We have seen - and still have... - MCs with VTF around 1.2 to 1.5 (v.d. Hul among others). MC do NOT have ad decretum lower compliance than MMs. The skating force is - among others - a result of VTF, offset of the stylus towards the groove wall and total contact area of the stylus. Its becomes less with increased effective length and resulting decrease of tangential error. It is null at any zero error point and becomes more and less with increasing tangential error and decreasing to wards the next zero point.
Simple model.
The force is never constant - and should therefor be addressed by an inverse force which is itself variable in conjunction with the tangential curve of the given tonearm.
Not really complex - it just needs more than a plain stupid constant anti-force.
But nothing in our days is so clear as not to be neglected and denied by some.
I am positive that maybe Raul in his new upcoming tonearm-design will address this issue.
Of course we can always simplify things and we see a strong movement in this direction ever since the last 2 generations.
Why ?
Because it makes things cheaper to produce.
More profit made - less brain needed.
Simple story indeed. |
Dear Doug, lets not mistake the torque tension force (which is indeed a result off the offset angle at the headshell) or the J-/S-shaped form (featured on tonearms with detachable headshell) common on most pivot-tonearms (and seldom addressed....).
As many (not all) a tonearms do not feature any lateral balance device at all to counterbalance the torque tension of its armpipe, these all too often do indeed produce a movement on a plain record.
I have performed the test you suggested several times.
With my 12"+ tonearm and a cartridge with Q4-capable stylus the tonearm (... with correct applied lateral counter-balance and on a dead level TT) sits still (no inward move) at the 2 zero error points of the tangential curve.
Am I missing parameters?
Pure luck ?
Coincidence ?
Correct model ?
Whatever......
Fact is - as a selected handful (precisely...) of the bavarian routed A'goners do know very well - that sibilant distortion, inner groove distortion or "wandering images" are non-existent on the front-ends set-up by me.
And no - these aren't all FR-tonearms, but do include DaVinci, Kuzma 4P, Graham, SAEC, Micro MAX, Triplanar (to name the better of the pivot-designs).
9" to 12" which - by the way, Axel - can not really be distinguished in groups by their overhang.
And yes - exactly - what would we prefer?
A "simple" (but precisely designed and engineered - all too often forgotten as we are so accustomed to it - german car or a "complex" (....complex ? where ?) british one (and - oh, sorry - is there still any major british car brand NOT owned today (and improved in terms of reliability and performance by its new owner) by either BMW, Audi or VW .... Jaguar is owned by Ford isn't it?).....?
And yes, I know that the japanese cars are even more reliable - fact is that I still prefer 2-3 japanese born tonearms (which by the way did address the issue of torque tension producing lateral movement...) above any german designed tonearm. |
Of course my idea is wrong.
But that is always the case.
After we have agreed upon that and set it aside, maybe someone is willing - or not..... no problem (at least not mine) - to visualize what is actually happening aside from dogmas, simplified models, laws (which aren't what they used to be either) and small hills which became mountains (ever seen the nice movie with Hugh Grant who climbed up the first and came down the later?).
With all those clear models around, I really wonder why there still are so many complaints and discussions about inner groove distortion, off-angle cantilevers, wandering images and sibilants which pierce the ear.
With all those great anti-skating devices around.
Strange. |
Axel, the often cited law of friction by G. Amonton (who kind of re-discovered it 2 and a half centuries after its original "inventor" Leonardo) as the main "law" being the skating force in phono playback assumes, that the bearing of the tonearm is not able to *completely support* the resulting force towards the inner groove. This force is a result of the offset of the tonearms "head" and therefor the cartridge and its cantilever. This offset implies a force that would - if not compensated by bearing or lateral balance - swing the tonearm's "offset part" (the "right side" if view from the front towards the cartridge/tonearm head) downwards because it needs to find a stable position in gravity.
Thus resulting in a horizontal force on the inner groove wall.
So far so good.
And I agree with this of course.
This is true for most pivot tonearms.
But not for all I think.
Now what IF the bearing is able to COMPLETELY SUPPORT the resulting force.
It is obvious, that most uni-pivot tonearms and knife edge bearing tonearms (among others) can NOT completely support this force.
However - a rather long effective (12" is fine .... of course 16" would be better) tonearm with resulting LESSER offset and a left side lateral balance can (at least in empirical observations.....) almost (if not 100%) completely support that force, as it is compensated by lateral counterforce.
A completely balanced FR-66s with its lateral balance correctly adjusted and on dead level TT shows no skating force in the 2 zero points of the tangential curve.
2.7 VTF with a stylus even "sharper" than a line contact.
A SME 3012 with bronze knife bearing does show heavy skating even in the 2 zero error points.
Both tonearms adjusted for same tangential curve and running with the same cartridge (FR-7) on the same table.
Maybe this way I can illustrate why i still think, that the model ... maybe .... is a bit more complex as the initial anti-skating model we are used to.
BTW - I vividly remember that the anti-skating devices in former Thorens, some EMT and Dual turntables (among others of west german manufacturers of years gone by) showed at least 2 different anti-skating scales: - one for elliptical stylus, one for conical......... |
Axel, that is in the general accepted model I mentioned.
To illustrate the point:
an uni-pivot tonearm with no lateral balance and an offset (be it in the way of a S- or J-shaped pipe or an offset headshell mounting area on an otherwise straight arm-pipe) "head" would - if viewed from the front towards the cartridge mounted - "swing" down with its right side over the long axis till it finds a position in gravity.
This "down-swing" over the right side does cause the force towards the inner groove wall (left....- viewed from the front).
Now - if this obvious tendency is (just as a hypothesis...) completely (even the technical books aren't very detailed here, but the general term used - even in old AES literature - is, that the bearing in general does not "completely support (address)" this torque movement) counter-balanced at or in the bearing, we would see no longer an additional friction at the inner groove wall which would be rooted in the offset.
This model would indeed require a design which does feature a lateral balance option which would be able to counter-balance the downforce initialized by the offset.
The "actual friction force" we see on pivot tonearms is (I am careful now...) "maybe" not only a matter of the offset.
As this force is in my 30 years long experience quite different in different tonearm designs (mounted with identical cartridge and stylus and VTF) I believe (I am careful again....) that there is still more to it than just the force initialized by the offset of the pivot tonearm's geometry.
All I want to suggest (carefully....) is that maybe there is more and that we - maybe - settled to soon with an explanation which - maybe - does not address all parameters.
I will get a Wacom touch board next week - then I can draw the whole model and try to illustrate the point by graphics.
Cheers,
D. |
Hi Pär,
the vinyl is indeed kind of soften and expanding its surface due to the heat of the stylus .
That is an old problem noticed by record companies as long back as the middle 1950ies. Thats why records do suffer from repeated playback (especially single tracks played over and over again in a row - which BTW is a (smaller) problem with CDs too....) - the vinyl has no "time" to "recover" (read: return into its original form and cooling down completely).
Thats why it is so important - aside from recovering the most tiny detail information engraved - that the stylus is as perfect aligned as possible.
A misaligned stylus does obvious create much more "problems" to the softened vinyl groove wall.
An while friction may be linear to VTF, the pure kinetic force on the groove wall is a result of down-force divided by contact area. The largest contact area (and resulting lowest force on the groove WALLS (plural..) in A GIVEN RECORD is in the groove-compliant VTA.
Means - even if not all agree on the sonic benefits of a certain VTA for a certain record, it is in this very situation, that we have the least "pressure" (VTF divided by contact area) on the walls of the record groove.
Cheers,
D. |
