SpinGuard Alignment Protractor

Description

The SpinGuard Alignment Protractor is a precision laser-printed alignment tool that allows correct cartridge geometry to be set using three internationally recognised null-point calculation methods — Baerwald, Löfgren B, and Stevenson — without requiring a separate download, print, or geometry calculation. Cartridge alignment is the single setup step that most directly affects sound quality and record wear, and the most commonly performed incorrectly. A misaligned cartridge tracks at the wrong angle through the groove, increasing inner-groove distortion and stylus wear.

Three Null-Point Systems: When to Use Each

The choice of alignment geometry determines where on the record surface the cartridge tracks with zero lateral alignment error. Each system makes a different compromise between distortion at the outer groove, middle, and inner groove:

– Baerwald (IEC standard) — minimises peak distortion across the full record surface; best general-purpose choice
– Löfgren B — minimises total average distortion weighted toward the inner grooves; preferred for classical and long records
– Stevenson — minimises distortion at the innermost groove only; historically used by some Japanese manufacturers

What Is Included and How to Use It

The SpinGuard Alignment Protractor includes everything needed for a complete cartridge alignment:

– A3 laser-printed card at 250 gsm — rigid enough to use without a backing surface
– Three null-point grids pre-printed for standard 9-inch (222 mm) and 12-inch (295 mm) effective tonearm lengths
– Spindle location slot for precise platter placement without adhesive
– Overhang measurement scale in millimetres for setting stylus-to-pivot distance
– Stylus downforce scale for verifying tracking force with an external balance
– Step-by-step six-point alignment guide printed on the reverse

No download or printer required. Designed to be used once per cartridge installation and stored flat. Backed by a one-year warranty.