Gear & technology
Tonearm
Also called arm, pickup arm
The tonearm holds the cartridge and lets it track the record groove from edge to center while applying a small, set downward force. Its geometry, bearings and rigidity decide how accurately the stylus follows the groove.
Setting up a tonearm means adjusting tracking force, usually 1.5 to 2.5 grams, anti-skate to counter the inward pull of the groove, and alignment so the stylus stays as close to tangent with the groove as possible, exact at only two points across the record. Done badly it adds distortion and wears records; done well it is invisible.
Arms are straight or S-shaped and 9, 10 or 12 inches long; longer arms track with less angle error but need a larger deck. The arm’s effective mass has to suit the cartridge’s compliance, which is why not every cartridge suits every arm; low-compliance MC designs usually want a medium-to-heavy arm. Most turntables come with an arm matched to the deck; separate arms are a high-end pursuit.