Tonearms with no anti-skate adjustment


I am in recent possession of a Grace 704 uni-pivot tonearm, which has no anti-skate adjustment. This is not optimal IMO, but should I really be worried?
128x128jdjohn

Showing 8 responses by cleeds

williewonka
Anti-skate is reqired to counter the effect of the "drag" the stylus/cartridge exerts on the arm while playing a track.
That is mistaken. Anti-skate is used to compensate for a force that an offset pickup arm exerts that gives it a tendency to "skate" towards the spindle. That’s why true linear tracking arms don’t include anti-skate adjustment.

Some manufacturers discourage the use of anti-skating force, including some who include antiskate adjustments on their arms. VPI is one such example.

Opinions by audiophiles about the necessity of using anti-skate are divided. Surprise! The best approach is to decide for yourself. My preference is to use anti-skate, but in an amount much less than is typically indicated on a pickup arm.
stringreen
If you hear a bit of mistraking add a tiny more VTF. (you can do that by slightly lowering the tail end).
Are you confusing VTF with VTA?

Lowering the arm with reduce either one, so I think you're mistaken.
moonglum
Unipivots are generally designed to be as stable as that configuration permits. This means that ”lowering the tail end” increases downforce not decreases it as you have suggested.
It isn’t clear what you mean here when you use the word "downforce." If you lower any statically balanced pivoted arm - regardless of bearing type - you will decrease VTF, all other things being equal. That’s just simple physics, and what I was trying to clarify.

testpilot
VTF is maximized when the stylus/record interface and tonearm bearing are horizontally inline with one another. Any deviation from this reference will reduce VTF.
Sorry, but this is mistaken and makes no sense.

VTF stands for "Vertical Tracking Force." By definition, it is measured at the stylus. As you raise the arm - all other things being equal - you will increase VTF. This is simple physics. Consider two people carrying a heavy item up a stairs. Who has the heavier load: The guy at the bottom of the stairs, or the guy standing a few stairsteps higher?

You can measure VTF using a proper gauge and see for yourself the change as you raise and lower the arm.

I do agree that keeping the stylus and the pickup arm bearing on the same plane improves tracking as opposed to designs that place them on different planes (again, all other things being equal). But that really has nothing at all to do with VTF. Perhaps that is what is causing your confusion.
lewm
... the magnitude of the skating force will vary based on the stylus shape, the degree of tracking angle error, the headshell offset angle, and the modulations in the groove wall. This is why no one value of anti-skate force will be absolutely correct across the surface of any LP. It’s a moving target.
I agree. The best one can achieve with anti-skate is a compromise, a happy medium.
Any tonearm which is designed to be mounted so that the stylus tip overhangs the spindle will develop a skating force at all points across the surface of the LP. There are no exceptions. Therefore to say that some tone arms do not need anti-skate is to me a bit of self deception. If you cannot hear the effect of the absence of anti-skate, nevertheless there is a skating force.
Agreed! That's why I prefer to use anti-skate, even if there is no one, single perfect setting. There is no reason to allow perfect to be the enemy of the good. 
moonglum
Your beliefs are contrary to those who have measured the force at the elevated stylus point and compared with “horizontal” arm measurements for VTF.

Have you performed such measurement to confirm your belief?
It isn’t clear what you’re asking here.

I can tell you that - all other things being equal - if you increase the height of a statically balanced pickup arm, you will also increase VTF, however slightly. Similarly, if you decrease the height of a statically balanced pickup arm, you will decrease VTF, however slightly. You can easily measure this with a proper VTF gauge.

I’m really surprised that there is any debate about this. It’s pretty basic geometry and physics, and easily measured.

And yes, I’ve measured it.
dover
If the arm is level, then moving the pivot point up or down moves the counterweight closer to the pivot ...
It isn’t clear what you’re claiming here. It doesn’t make sense if what you mean is that raising the arm brings the counterweight closer to the pivot. The distance between pivot and counterweight will remain the same if all you do is raise the arm.

You can use a VTF scale to confirm that if you raise a statically balanced arm, you’ll increase VTF and if you lower the arm, you’ll decrease VTF. That’s easy to measure.

To be fair, the VTF doesn't really change much, based on my measurements.


dover
... if the arm starts at level then ... Moving the back of the arm up and down at the back will move the centre of mass forward towards the mounting position ...Therefore IF you start with a level arm, the VTF will increase with either up or down motion because the centre of mass moves towards the cartridge in both instances ...
That’s a fanciful theory. Why don’t you try and actually perform this test and measure the result? If you do, you’ll find your theory is mistaken. It’s as simple as that.