Setting anti-skate

Here are some other ideas I have heard about. For arms that have replaceable headshells, you could devote one to an Orsonic Skating Force Guage, if you could still find one. Another idea is to use a record that has no grooves at all on one side, such as the 3-sided Keith Jarrett album, and check skating at various points across the record, choosing the best compromise. But I think that the easiest method is just look at the stylus at the moment it touches the record, and adjust anti-skating for minimum stylus deflection.

How can we say that groove modulation makes a difference in skating force, then also say correct anti-skating is adjustable by eye? If these are both true then we should be able to see the stylus move sideways when a song starts. Since I am quite sure we CANNOT see this, then one of these two concepts is wrong. Which one is it?

Its not that widely spaced is better. The widely spaced tracks indicate that these are very highly modulated (in other words very difficult to track). So, presumably, if anti-skating is optimized, the cartridge will track better through these grooves. But I don't think I agree that trackability is the purpose of antiskating. Its an indirect by-product of the purpose: to provide equal force at both sides of the groove. So we need to come up with the best way to observe that equal force is indeed being applied, particularly for our favored low-compliance cartridges with which we cannot really see the deflection. What about installing a cheap high-compliance cartridge, and using it to calibrate the anti-skaing method? Track this cheapo at exactly our intended force, and note the deflection when the needle is dropped on the record, at various points on the record. Then adjust antiskate, and switch cartridges.

Using a record without grooves to check anti-skating is not "against the law of physics". Think about it a bit more. The friction of the record against the stylus tip is what causes an inward force upon the cartridge. Anti-skate attempts to balance this with an equal-and-opposite mechanical force. With no anti-skate, a grooveless record will pull the needle inwards, and this motion will be obvious. With too much, the mechanical force will pull it outwards. If these are equal, then the arm-and-cartridge will not move in either direction. This concept was well accepted in the 60s and 70s, exactly because it IS consistent with the physics of the forces applied. Now, is it perfectly accurate...no... because the friction of two groove walls is not identical to the friction of a flat surface. But if there is no force side-ways, because all side forces are equalized, then it is ONLY the down-force that is causing friction. Furthermore, think further. The variation of skating force must be extremely variable as the arm moves across the record, because velocity becomes slower as we approach the center and tracking angle varies. So, any mechanical anti-skate device cannot achieve accuracy across the entire record. Whatever we settle upon is a gross approximation, no matter how we measure it.

And what about azimuth? This is more critical to sound than AS, and (unlike AS) has one best adjustment position. Are we all adjusting this too?

Thank you Winegasman for your confidence in my ideas. Thommas and Rmaurin were so quick to condemn the blank record approach, that they apparently don't realize its the best idea mentioned yet. Of course, a test-tone record and distortion analyzer is absolutely the only fool-proof method. These have been the accepted methods for longer than the 25 years I've been an audiophile. All the other ideas are difficult and non-repeatable... judgements based on VERY subtle sensual observations. After any reader of this thread tries the visual (stylus notion) and listening (mistracking in one channel) ideas, he may just get frustrated by inconsitent results.Then I think he may appreciate the simplicity of the blank record technique.

Nsgarch, thank you for your detailed technical analysis, but your understanding of coefficient of friction is wrong in EXACTLY the way it brings you to the wrong conclusion. Your analysis utilizes your personal logic instead of an application of physics. So, all of your 3 numbered points fall apart from an incorrect primary assumption. Your problem is that friction is actually INDEPENDANT of contact area. If you don't believe me, look up the equation for friction on the internet: F=uN. frictional Force = coefficient of friction times Normal force. Nothing about contact area. Diamond touching vinyl has the same coefficient of friction whether touching by the "bottom tippity tip" or the entire playing surface of the groove. And, the normal force is determined only by VTF, again independant of contact area. 1) vinyl has no coeff by itself 2) diamond has no coeff by itself -- they have a coeff TOGETHER that is constant and (3) INDEPENDANT of contact area. The smaller contact area of a blank record just means the same force becomes a much higher psi (surface pressure). So there IS definitly a frictional force, it is close to the force in a groove, and it is adjustable by anti-skaing. THAT is why the arm will go racing towards the center unless an equal and opposite force in applied by the anti-skating feature. If you set a needle down on a stationary blank record it will NOT slide towards the middle. But it may slide towards the outside, because now the anti-skate is unopposed.

Nsgarch and I are getting closer to agreement now, because I agree that different stylus shapes require different anti-skating force, and that a blank record must also be different than a real groove. The interaction of the stylus with groove undulations definitely makes a difference in skating force, which agrees with other comments heard here that skating force varies with groove modulation. I just think a blank record is a good starting point, before fine tuning of the anti-skating. I think its about as accurate as trying to observe motion of the needle upon dropping it into a groove. Its a lot more difficult to see the needle move a little, than seeing an arm skaing across a smooth record! Plus keep in mind that many cueing devices don't exactly set the arm down straight AND many records have a little out-of-round wabble. These will give the stylus some sideways motion also. Furthermore, we need to figure out a final step which ACCURATLY provides the real adjustment. I think the only way to do this right, is by playing various test tones, and comparing right and left channel distortion on a distortion analyzer. Without this equipment, I agree that listening is the next best way.