Actual waveform of IGD for an elliptical vs MR/ML stylus

[aussievintage]

 

First time I have seen this (heard it often though  )

 

In this discussion  https://www.audiosciencereview.com/forum/index.php?threads/not-loving-my-at740mlx.58031/page-3   someone has posted an actual waveform comparison.  This one is at 20kHz, and it so clearly shows the elliptical stylus' "curvature overload" as it tries to squeeze through the high frequency grooves at the end of a record.  The ML trace otoh is a better sinewave.

 

Edited November 1, 2024 by aussievintage

[cafe latte]

This is from the Orbray Website. It compares their Shibata ( line contact) to a micro ridge both outer and inner grooves.

A 0.2x 0.7 elliptical has the same minor radius as a Shibata so it will perform on good new vinyl the same as a Shibata. 

[aussievintage]

1 minute ago, cafe latte said:

This is from the Orbray Website. It compares their Shibata ( line contact) to a micro ridge both outer and inner grooves.

A 0.2x 0.7 elliptical has the same minor radius as a Shibata so it will perform on good new vinyl the same as a Shibata. 

 

Yes,   the inner groove deficiencies show up in the frequency response for sure,  but I found it interesting that you can see the bend in the actual waveform, of the stylus tip being squeezed each cycle.  The distortion in the sound will be horrific.  Certainly accounts for the noise we hear in the high frequencies when IGD is apparent.

[cafe latte]

The internet myth that Shibata is better is totally busted if you look at the above plots.

Chris