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Setting the Anti-Skating – Two Solutions
Anti-skating is one of the least understood forces acting on a tonearm. Skating
force is created by friction between the stylus and the record, causing a force
vector in a direction towards the center of the record when the headshell of the
tonearm has an offset angle. Putting a stylus down on a flat, groove less record
will cause the arm to move toward the center of the record. Arm manufacturers
have tried to compensate for this force, but that is impossible because the force
is constantly changing as the music and velocity change.
VPI has conducted careful listening tests and determined that every tonearm we
tried sounded better with its mechanical anti-skating disabled and the tracking
force very slightly increased..
VPI has a unique solution to anti-skating: the coiled wire of the JMW Memorial
Tonearm acts as a spring and pushes the arm back without affecting the sound
quality. You now have the option of installing a mechanical anti-skate for those
that want it.
Adjust the counterweight so there is no down force on the cartridge.
Swing the tonearm toward the spindle and release it. The arm should swing
out toward the outer edge of the turntable.
If you try adjusting the anti-skate with a groove less
record, you will ruin the twist in the tonearm wire
and void your warranty. Do this with the mechanical
anti-skate if you want that much anti-skate.
If additional anti-skate is wanted you can go to the mechanical anti-skate
we supply.
Setting the Tracking Force and Tonearm Height
Tracking force is adjusted by moving the tonearm counterweight forward and
back on its shaft. If your cartridge is heavy and the counterweight is all the way
back, you can order a heavier weight from your dealer.
The JMW-9T Tonearm does not have a built-in tracking force gauge. We
recommend that you use a Shure Stylus Force Gauge or good digital gauge.
Place the gauge on the platter (no record)
Loosen the set screws in the base of the tonearm and raise the arm so it
looks parallel to the platter when it is on the stylus force gauge. To adjust
the arm height, loosen the setscrews on the base of the arm assembly and
