This article is from the rec.audio.* FAQ, by with numerous contributions by Bob Neidorff others.
Stylus tracking force is typically adjusted at the back of the
tonearm with a knob that is calibrated in grams at the stylus
tip. With the control set to zero, the stylus should sort-of
float above the record surface. The control is then increased
to the number recommended by the cartridge manufacturer.
Do not, under any circumstances, use a lower than recommended
force, as the cartridge may lose the ability to maintain
contact with the groove wall on passages of large amplitude.
This WILL result in RECORD DAMAGE.
If you want the best possible tracking and sound quality, you
will want to fine-tune the tracking force. Use a test record
and listen very carefully, or get the help of a good dealer
with a battery of instruments.
 
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