headshell

A headshell is the detachable front section of a turntable's tonearm that carries the cartridge and stylus. It provides the mechanical interface for mounting the cartridge and the electrical interface that connects the cartridge's terminals to the tonearm wiring.

Most headshells are designed to accept a standard 1/2-inch (12.7 mm) cartridge mounting pattern and attach to the tonearm with two screws. Inside, flexible leads connect the cartridge to six contact wires that run to the tonearm's wiring harness, typically color coded for left/right channels and ground.

Materials and construction: Headshells are commonly made from aluminum, magnesium, carbon fiber, or reinforced plastics. They are often available in different masses to adjust the tonearm's effective mass and resonance. Interchangeable headshells allow cartridge swapping without replacing the entire tonearm.

Mass and resonance: The headshell adds weight to the tonearm and thus affects tracking ability and resonance with the record. A heavier headshell lowers the effective resonance frequency, potentially limiting cartridge choices; a lighter one raises it and can improve tracking with low-mass arms. The choice depends on cartridge type and tonearm design.

Compatibility and alignment: Cartridges are mounted to the headshell and then aligned using standard protractors and alignment measurements before being attached to the tonearm. Some headshells offer azimuth or vertical tracking angle adjustments; others provide fixed interfaces. Proper mounting and wiring are essential for optimal channel balance and signal quality.