Stylus 'zenith' angle & SRA (Stylus Rake Angle) should be professionally checked - according to Michael Fremer (ANALOG PLANET)

'Zenith' certainly, should not be a problem I think you should expect with the high quality cartridge.

SRA - I've yet to be convinced that 91-92deg SRA is the magic 'setting', myself.
(Esp. now that I'm using a London Decca cartridge with SRA that is ~75deg.)

For one thing, some stylus profiles have contact line angle that may not be in line with stylus shank angle, eg Shibata (below).

By all means do initial set-up using such measurements, but IMO still continue to fine-tune by ear I say.



('Zenith' angle, obviously poor quality cartridge manufacture.)


(Unusual, but necessarily 'incorrect', SRA for a conventional cantilever type cartridge.)

DarkLantern blog - darklanternforowen.wordpress.com

With all due respect to Mr Fremer: What a couple of useless measurements ! I would suspect most vinyl enthusiasts would have no way of measuring those specifications let alone in adjusting for them.

He is also guilty of some really incorrect statements. See below and my bold.

Everyone reading this who installs his or her own cartridge uses the cantilever as the guide for setting zenith angle, which is what you set after you get the correct "overhang". Unfortunately, as the photo at the top indicates, even that setting is unreliable! The costly microscope used to produce that image shows an expensive cartridge's stylus inserted into the cantilever at an angle that's around 4% "off". The result is that the stylus reads one side of the groove before the other. This problem gets exacerbated the further towards the center of the record the arm travels, resulting at the very least in gross phase distortion.

When coupled with the picture it is clear that the stylus is out by some 4 degrees in a front/back orientation and not in a left/right channel orientation. Gads, I hope you see what I mean. Anyway I stopped reading at that point.

Not wishing to specifically defend Mr Fremer but to be fair....

1) He does recommend sending your cartridge to Wallytools & using their services for an initial, professional inspection, to confirm the manufactured angles of your stylus..

2) When MF refers to this stylus being 4% 'off' (actually ~5%), I believe I'm correct in thinking that he refers to the top pic, ie the rotation of the stylus cross-axis line across its LHS & RHS contact points (he calls this 'zenith'). The contact point on one side of this stylus sits 'forward' of the other (as the groove travels past). In this case, it's the side closest to the record outer edge - so logically, MF concludes that this outer side of the groove (the RH-channel) will be 'read' before the other (LH-channel).

DarkLantern blog - darklanternforowen.wordpress.com

Owen, you are right! The moral of that story is never read an article when knackered and late at night!

On the other hand... introducing SRA into a conversation round Zenith is distracting!

His point about mounting the diamond is essentially a punt - has anyone done a survey on how many cartridges have wonky mountings (I nearly wrote wally). So his advice to get it checked is probably really good, especially when you are investing oodles of dosh!

Gosh. Microscope pics like that make you think about all sorts of ills with styli being dragged over a piece of plastic. The force to accelerate such a relatively large mass of aluminium from such a small area of diamond must be huge. Zenith on this particular stylus is far out. I wonder which cartridge that was, and how typical an error like this is?
Just go high res digital.....😄

AMR-iFi R&D

Feb 13, 2021 20:21:23 GMT 12 colinf said:

Just go high res digital.....😄

..SOAP.!!!.......😁😋

Never play Leapfrog with a Unicorn.