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What is more accurate , the fozgometer or the diplay of the oscilloscoop

Would like to know sure about the azimuth of the cartridge ,a visual check first ,than the result of the fozgo , just a bit differance between the left and right channel , than both channels in mono , green led and a little shiny of the red led for the right side .Than looking at the display of my techtronix dual beam oscilloscoop , both channels 
even , no differance in amplitude . Playing a piece of music , perfect ! What is true ? Can you adjust your cartridge with the fozgo with results in the description ? Ofcourse I did the calibration of the fozgo.

hansk46
lewm
13,452 posts
 
Thanks for your response, Benjie.
folkfreak's avatar
folkfreak
1,349 posts
 
@stringreen -- not sure why the method for making the azimuth adjustment (ear of meter) makes any difference to how fiddly it is to do. Even with a fozgometer you're going to need to make azimuth changes and also go above and below the "correct" setting to get there. Maybe it's just a case of some arms are harder to adjust than others?

Anyway as to the question of ear vs measure I own a foz and use it to get the azimuth in the ballpark and then fine tune by ear

This stuff really matters, and the level/mirror method falls short for those cartridges (like the majority of Air Tights ime) that are not mounted that accurately. At the last Newport show 2 out of 3 AirTights (including a magnum opus) had to be mounted with a visible cant to get the azimuth right -- my PC-1 is no exception, it sounds best lilting 10-15 degrees off to the right
lewm
13,452 posts
 
folk freak,  "Sounds best" or measures best?
Because THAT much tilt indicates rather poor quality control during cartridge manufacture or inaccurate measurement of crosstalk.  Since Air Tight cartridges are hardly in the budget category, if I owned one that needed that much tilt to deliver decent crosstalk figures and assuming the measurements are accurate, I would send it back to its makers.

When you tilt by 10-15 degrees, you are putting seriously uneven wear on the stylus tip and you may also be damaging grooves, depending upon the shape of the stylus tip.

I've written this before, so please forgive me for being redundant, but in setting azimuth, one might choose to go for equal amounts of crosstalk in both directions, L to R and R to L.  Or one might choose to go for the least crosstalk, regardless of whether the db are equal in both directions.  I've been setting azimuth electrically for years, using a Signet Cartridge Analyzer and their test LP, plus my Triplanar tonearm which permits very easy adjustments.  In all my experience, those two possible goals are never coincident with each other, which is to say that if you want equal crosstalk, the absolute db of crosstalk will be higher (more crosstalk) than if you just go for the least amount without worrying about equalizing.  I believe the Foz is designed to equalize crosstalk.  Sometimes going for equal crosstalk requires a lot of tilt, which I don't like to live with, for reasons mentioned above.

folkfreak's avatar
folkfreak
1,349 posts
 
lewm -- turns out I’m lousy at estimating angles in my head, taking a quick measurement (using my iphone level app) it’s clear that the tilt I was seeing on my headshell is more of 2-3 degrees at most -- odd how small deviations from horizontal seem much larger than the same deviations from vertical -- must be something to do with how we are wired to examine the horizon?

Anyway as what we are trying to do is get the stylus exactly vertical and given how probably difficult it is to be sure you’ve mounted a tiny bit of diamond into a shank of boron/aluminium at exactly the right angle it’s not that surprising that even $15K cartridges can be off.

I do agree however that it’s disconcerting to see and part of the reason I’ve recently moved away from this brand of cartridge
lewm
13,452 posts
 
folkfreak,
Crosstalk will depend upon the angle that the distal end of the cantilever, where the coils are mounted in the case of an MC cartridge, makes with the stationary magnet structures that thus create the stereo signal.  That part of the cartridge, the business end, cannot be seen from without; we can't know what's going on there, in most cases,without taking the cartridge apart. (Maybe you can see it in a van den Hul; I never checked.)  If the magnets are not symmetrically arranged around the moving end of the cantilever, then that will affect crosstalk dramatically, in a negative way.  Since it is possible to build a budget cartridge that is nearly perfect (not absolutely perfect, but nearly) in this regard, I would posit that needing a significant tilt (optimal azimuth several degrees off horizontal) is not acceptable in any very expensive cartridge.  I guess one could argue over the definition of "very expensive", but $15,000 is off the charts.
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