Tonearm Alignment Calculator

Enter the pivot to spindle distance or effective length of your tonearm to calculate optimized alignment geometry. You can further optimize your alignment by entering alternative groove radii based on max/min measurements from your own record collection.

Note

• Figures for inner and outer groove radii relate to the limits of modulated grooves i.e. those with recorded sound

• Distortion figures are calculated from samples of tracking error in the modulated groove area

Comparison of alignment methods

Stevenson - a variation on Löfgren geometry optimized for low distortion at the inner groove at the expense of increased distortion elsewhere. compared to Baerwald or Löfgren B you will get lower distortion for the last few mm of the record

Baerwald (identical to Löfgren A) - minimizes and equalizes distortion at the three weighted tracking error peaks resulting in moderate distortion between the inner and outer grooves

Löfgren B - minimizes distortion between the inner and outer grooves resulting in the lowest average RMS distortion at the expense of slightly higher distortion close to the inner and outer grooves

Term definition

Below is a simple illustration showing the relationship between the terms used on this page

Mounting distance - spindle centre to mounting hole centre (normally the same as pivot to spindle distance)

Pivot to spindle - spindle centre to horizontal pivot point of the arm

Effective length - stylus tip to horizontal pivot point of the arm

Overhang - stylus tip to spindle centre overhang

Offset angle - angle between cantilever and a line drawn between the stylus tip and the horizontal pivot point of the arm (not to be confused with headshell angle)

Inner / outer null point - the two points on the arc of travel at which the stylus is perfectly aligned to the groove i.e. null tracking error

Inner / outer groove - the limits of the modulated grooves specified by IEC as 60.325 and 146.05mm and DIN as 57.5 and 146.05mm