How to set SRA after determining true vertical?

Wow, this thread is really full of important information. Related to this topic, I have recently heard of a “theory” from my friend that I have never heard before, and I am kind of skeptical about it. So, I think this is the place to find out the answer. Since I am a bit confused, please bear with me. His “theory” goes like this:

1, Due to the different cutting angles used by different labels (and the cutting lathe they used), Decca, EMI, etc., you will need different SRA/VTA to play the different labels of LP.

2, Different cartridge makers manufacture their cartridges with different build-in VTA (he said something like 20 degrees and 22 degrees). As such, to have a perfect playback, you need to match the cartridge (with it’s build-in VTA) to the record labels. For example, say an Ortofon, with 20 degrees build-in VTA, will fit the Decca, and another brand of cartridge, say a Clearaudio, with 22 degrees of build-in VTA, will fit the EMI etc.

3, As such, you’ll need at least 2 cartridges to ideally/accurately playback the different labels.

I am very skeptical of this “theory”, and I think this forum is the perfect place to ask whether there is any truth to it.

Thank in advance

Michael

A wrong theory carried to a ridiculous extreme.

Actually, it's a right theory carried to a ridiculous extreme.

A simpler solution is a tonearm with adjustable height. Then you can use any cartridge you like and play any record you like, while matching SRA.

A simpler solution is a tonearm with adjustable height. Then you can use any cartridge you like and play any record you like, while matching SRA

Yes -- but by adjusting height you'll be changing the stylus overhang. As you note, having two arms is the right way -- but an extremist solution!

I am still looking for an article or picture that demonstrates that angled cutting head produces an angled cut. Has the angled groove been measured? All I have ever read is that it was just assumed.