Help! Antiskate with only a weight...no dial, and she's skating away!


I have a project rpm 10 carbon with 10cc evolution tonearm that has a weight on a string for antiskate. There are three notches on which to attach the string based upon the tracking force range of the cartridge. I currently have an ortofon cadenza bronze tracking at 2.5g and have the antiskate weight in the appropriate notch (according to the Pro-ject manual) from which it hangs. The table is level--checked and adjusted to ensure. The tracking force is at 2.514g (the range for the cadenza is 2.2-2.7 with 2.5 suggested by ortofon) checked with a digital scale (Riverstone Audio digital scale). The soundstage sounds great, vocals are centered, other instruments are placed in space according to the recording... Also the alignment was carefully set up using the WallyTractor and is spot on. 

But sometimes when I lower the stylus to the lead in groove, it will slide very quickly towards the spindle as though no antiskate were present (it doesn’t skip over the record, it falls into the first song groove--and yes I have confirmed that the stylus is present). But it’s a big jump vs just sliding into the groove.

So I found a blank side of an album and lowered the stylus onto the surface and it immediately slid all the way across the surface towards the spindle as though no antiskate were in play. I then disengaged the antiskate weight and experienced the same (expectedly so). But there seemed to be little or no difference between antiskate being engaged/disengaged.

So I engaged the weight again and lowered the stylus, but this time I placed a little extra force on the weight with my finger and was able to get the tonearm to stay in position--applicable antiskate force in play with this extra force. Of course, I have no way of measuring how much extra weight I applied.

The help I need:
Why is the recommended antiskate parameters set by pro-ject seemingly having no effect?
Is something else wrong?
The table and tonearm are obviously manufactured to handle this level of VTF, no?
The tonearm wires don’t appear to be impeding the arm movement.
What can I do to remedy this?
Do I need to do something to remedy this?
I wonder if I’m causing harm to the cantilever with what appears to be no antiskate, yet the music sounds great and the Analogue productions test LP record antiskate tracks "sound" equal to my ears. (But my ears aren’t young anymore, so I don’t think I can place full confidence in that audible test).

Any thoughts, suggestions would be greatly appreciated.
cabalaska

Showing 3 responses by dover

 If you can't hear a difference it makes no difference.
That statement is totally illogical.

@cabalaska
Please do this test.

Remove platter.
Remove antiskate weight.
Balance the arm/cartridge to zero - so the arm is floating.

If the arm at zero balance, with no anti skate floats in or out then the arm mount is not level.

This could be the cause of your problem.
Often times turntable arm mounts are not on the same plane as the platter, which means if you level the platter the horizintal arm bearings are not level.
@stringreen

I suggested this to check that the arm was mounted on a level base and there is no dominant drift in or out.
I have seen some TT’s where the armboard was not level and anti skate had to be very high to offset the drift.
From the video he does not have a problem with the arm - so that means alignment or other cartridge set up must be the issue.
I do notice that the arm tends to drift back to centre of the horizontal travel in and out - this could be an indicator of some force exerted by the internal wires.

@cabalaska


I went back through your posts again.

Does the skating to centre only occur when you first lower the arm ?

If so check that the arm lift lowers in time - lower the arm and check there is a gap between the lift and the bottom of the arm when the stylus reaches the record..

Sometimes if the armlift is too slow then when the stylus reaches the record, if it is not completely clear and the cartridge effectively is trying to track at less than the tracking force set because the armlift has not fully lowered.

You can check this by watching the gap between arm & lift lift when you lower the stylus.