Stylus Force Guages - why extreme accuracy?


I am under the impression that, when setting up a phono cartridge, one sets the tracking force to the manufacturers recommended force, and then dial-in the final force by ear. If that is the case, then why are extremely accurate electronic stylus pressure gauges popular when the force is most likely going to change during final adjustment by ear? The Sure SFG-2, costing $25, has worked great for me to ball-park the initial tracking force before final tweaking. So, what benefit is the Winds ALM-01, costing $800, going to provide? Is it important to set the initial force to within a tenth of a gram, when that will change during final tweaking? What is the procedure those of you who own expensive gauges use for final adjustment by ear?
128x128seasoned
Most cartridge manufacturers have a recommended tracking force range, which allows for a bit of leeway plus/minus. I have used a Shure SFG-2 gauge for more than three decades, and have found it to be very accurate when checked against much more expensive digital gauges.

I am confused a bit by your comment about making final tracking force adjustments by ear. Are you referring to VTA (vertical tracking angle)? One DOES make final VTA adjustments by ear (after initially setting the tonearm to level), but I have never heard of making tracking force adjustments by ear. Seems to me that would mean there is no need for accuracy from the tracking force gauge.
I do VTA and VTF by ear. Use the gauges to get close. Ear for final dialing in....
Jfrech - Me too. Sdcampbell - may depend on your particular components, but on the tables and carts I've played with, lighter tends toward a more detailed sound and heavier toward a more romantic presentation. My by ear adjustments have stayed within the manufacturers recomended range but sometimes at the heavy end and other times toward the lighter.
Sdcampbell,

Me three. Both VTF and VTA/SRA can be fine tuned by listening, assuming your rig and ears are interested of course. :-)

Lloyd Walker's well-written guidelines are worth reading: http://www.walkeraudio.com/fine_tuning_your_turntable.htm

FWIW, we also adjust antiskate, azimuth, impedance and even drive belt tension by ear. VTF changes are just as audible as changes to these other parameters.

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Seasoned,
Metralla's explanation is also why I have a .01g scale.

When the weather changes and/or I swap cartridges I want to dial in a baseline VTF quickly. On my tonearm I need to set VTF within .05g or so before I can use my fine VTF adjuster.

For me a .1g scale would be too coarse. If it read (e.g.) 2.0g, all I'd know is that I'm "somewhere" between 1.95g and 2.05g. With many cartridges a range that wide is so vast you might as well not use a scale at all. My main cartridge has a sweet zone for VTF that is .02g wide at most. Setting it up without a good scale could take hours, instead of minutes.