What is you tonearm’s Maximum Distortion?


I’ve been playing around with different cartridge mounting, as a Grace arm the plinth of my Lenco cannot be mounted at the recommended pivot-to-spindle distance of 222mm (closest it can get is 225mm).


My best figures in theory seem to be:
Max. Tracking Error: 3.51 degrees
Max. Distortion: 1.21 %
Average RMS Distortion: 0.73 %

This is with: P-t-s 225mm; overhang 11mm; offset angle 19 degrees.

What are your figures for your setup?

fusian

@rauliruegas 

Forgot that if you want lower distotion figures then and using Löfgren A alignments its tonearm parameters set up are:overhang  21.58mm and offset angle  24.8°.

Where the maximum error  0.94°   maximum distortion  0.33%  and average distortion  0.22%.  All these for your P2S  225mm.

 You need two additional parameters to make the tonearm/cartridge set up and achieve those figures of lower distortion levels and that I don't gave you and are the null points that are: 80mm. and 126mm. not the one you are using today.

are the three quoted sets of numbers referring to the same setup?  

Like Lew, I am skeptical of the accuracy of the 'calculated' distortion numbers since the whole description is to vague. @nrenter  posted a screen grab to John Ellison's Excel spreadsheet.  which can be found on the Enjoy the Music site. This file has the description below of what the calculated percentage distortion refers to.

   Tracking Distortion (Column D) is based on dividing tracking error by groove radius; this is also called weighted tracking error.  Be advised that these numbers are scaled   so that they represent actual percent tracking distortion at a stylus tip velocity of 10 cm/sec.  In other words, the number 1.0 in Column D represents 1-percent distortion.

dave

@rauliruegas 

Since we are considering the theoretical, your proposed alignment simply looks like Löfgren A if you cheat the inner groove radius to 75mm and the outer groove to 143mm which is not realistic for all but the smallest selection of music.  Distortion at the 60.325mm inner groove point will be a fair bit over 2%

dave