I'm new here.
Polarity inversion of one channel in the Westrex system, to force lateral modulation of L+R, is not often discussed.
Here is an article I wrote at Lathe Trolls which may prove useful.
"Vinyl Polarity Relationships in the Westrex 45/45 System" https://www.lathetrolls.com/viewtopic.php?f=1&t=6661
(Unfortunately the gifs in the Lathe Trolls article no longer animate. Here is the original link:
https://www.vinylrecorder.com/stereo.html)
I see the crosstalk measurements made on a number of cartridges posted here. My question is what is the crosstalk polarity?
A Stanton 681 playing a CBS test record has out-of-polarity crosstalk.
It will sound wider, for a given crosstalk measurement, than a cart with in-polarity crosstalk.
Is it the cutter head, the cart or both that determine this?
I haven't found any real data.
We learn in the Lathe Trolls post that the Ortofon cutter head can produce crosstalk of either polarity.