Turntable Cartridge Alignment Protractor: SteinMusic Achat 1

Why use a cartridge alignment protractor?

A cartridge only sounds calm and clear when it sits in the right place and at the right angle in the headshell. Even one millimeter out leads the stylus through the groove at a slant. The result is audible distortion and uneven wear on stylus and record.

The Achat 1 turntable alignment protractor makes that position visible. Place it on the platter spindle, lower the stylus onto two marked null points, and fine lines show whether the cartridge sits straight. Overhang and offset angle are set in a few minutes.

Designed for where the music is

Classic geometries are calculated for the groove all the way to the innermost edge of the record. On most records, though, the music ends earlier. The Achat 1 therefore uses its own OTA® geometry (Optimum Tracking Angle), a two-point alignment developed specifically for LPs, with null points further out at 74 and 128 mm. The largest deviation of the stylus stays around 1.2 degrees, compared with up to 2.1 degrees after DIN alignment. Distortion caused by tracking error drops by up to 80 % compared with DIN-oriented protractors. The error is spread more evenly across the side, for calm playback from the first track to the last.

Listening: what changes

Calmer playback: less distortion, voices and instruments stand more clearly in the room.

Even across the whole side: the stylus follows the groove from the first track to the last with little tracking error.

Gentle on stylus and record: the stylus sits evenly in the groove and wears more evenly.

Quick to repeat: every time you change cartridges, the alignment is checked in a few steps.

Why not a printed protractor?

A printable paper protractor is a reasonable place to start. A printer rarely scales to the exact millimeter, though, paper bends, and the center hole sits loosely on the spindle. As a cartridge alignment tool made of anodized aluminum, the Achat 1 stays flat and dimensionally stable, fits the spindle snugly and gives the same result at every cartridge change.

Design & use

• Anodized aluminum, dimensionally stable and accurate for years, handmade in Germany.
• OTA® geometry (Optimum Tracking Angle) with null points at 74 mm and 128 mm, designed for the part of the groove that carries music.
• The OTA geometry needs more overhang than a DIN alignment. The cartridge must be able to move about 3 to 4 mm further forward in the headshell than usual. If that is not possible, the tonearm pivot has to move closer to the center of the platter.
• Parallel grid lines to align the cartridge at both null points.
• A tip from our workshop: tape a mechanical pencil lead to the front or underside of the cartridge, at a right angle to the cantilever. It extends the edge and makes it easier to see whether the cartridge runs parallel to the lines.
• Keep the turntable switched off while you align. Lower the stylus gently, the cantilever is delicate.
• Suits almost all pivoted tonearms. Tonearm height (VTA), azimuth and tracking force are set with other tools.

For a step-by-step walkthrough, read our guide How to Align a Turntable Cartridge.

Technical data

Material: anodized aluminum

Geometry: OTA® (Optimum Tracking Angle), own two-point geometry for LPs

Null points: 74 mm and 128 mm (marked R74 / R128)

Overhang: about 3 to 4 mm more than with DIN alignment

Largest deviation: around 1.2 degrees (DIN: up to 2.1 degrees), calculated for 211 mm mounting distance

Distortion from tracking error: up to 80 % lower than with DIN-oriented protractors

Suitable for: pivoted tonearms

Made: by hand in Germany