2. analog
  3. 1223246029

RS-3 owners: Seeking anti-skate help

Hello - I recently acquired the RS-3 headshell and attached it to my SME 3009 series II (unimproved). I followed the directions from the dealer to the letter and the sound, to date, is nothing shy of riveting, honestly. I am curious, however, if anyone with a similar set-up can comment on whether or not you are using the anti-skate rig. It is not 100% clear that the headshell completely compensates for the table's wanton tendency to pull the arm inwards, so I have set it up currently with the anti-skate weight in place, yet was wondering about the protocol of others, or if there is an official word on this?

Thank you for your help
nycwine1
lewm
13,427 posts
 
Thanks, Quiddity, for correcting me. I am guilty of believing the box that the RS-A1 comes in, rather than thinking about what is actually happening. It's good to know you're still out there somewhere. Would the pivoting headshell have any effect to ameliorate the skating force?
maxson
81 posts
 
I have the RS Labs arm, and it has no provision for anti-skating. Just another data point.
juliejoema
23 posts
 
There is no need for anti-skating force because the stylus is perpendicular to the armtube. The reason you need anti-skating for offset headshells is because the elliptical/line stylus is rotated by between 19 degrees and 23 degrees from the line that goes from the stylus to the pivot point. With the RS-labs arm, the stylus is always perpendicular to the line that goes from the stylus to the pivot point.

For an analogy, think of paddling in a canoe. If you are at the back of the canoe and place the paddle in the water directly behind the back/stern of the canoe, but put the paddle in 'at an angle', the canoe will turn to one side or the other. This is like the lateral 'skating force'. Think of the angle at which you dipped the paddle as the offset angle of a regular headshell.

If you place the paddle in the water perfectly perpendicular to the canoe, the canoe will slow down, but will not turn. This is like the RS-labs headshell. There is no sideways drag due to the stylus.

Now, the stylus does not follow the angle of the cutting lathe as it covers the vinyl groove as well as an offset headshell, which creates some phase error, but the RS-labs arm more than compensates for this with the lack of resonance from the actual armtube.

If you can't already tell, I love my RS-labs arm.
quiddity
119 posts
 
Juliejoma you have misunderstood skating force. It has nothing to do with the angle of the headshell except that this angle attempts to follow the offset of the pivot.

The stylus reaction force is a vector. The direction of the vector is a tangent to the groove. The vector does not pass throught the pivot of a pivoted arm. The distance between the vector and the pivot forms a torque arm with the stylus friction. This torque is the skating force. The length of the torque arm is equal to the linear offset of the tonearm (about 95mm in Baerwald's alignment) and this is nearly constant regardless of the angle of the headhsell / cartridge.
dopogue
1,773 posts
 
All well and good, Quiddity, but you seem to have misunderstood the wonders of the RS arm :-)

I can't blame anyone for doing this. You have to use the silly thing. I wouldn't have believed it either. Dave
More to discover