BaerWald vs VPI setup protractors


Which is more accurate? Recently I decided to check my setup on a Scout using both the VPI gauge and a Baerwald protractor. Using the Baerwald the overhang is dead on in both locations, using the VPI the stylus misses the mark forward by about half a millimeter. Can this small amount of variance have a sonic impact? Has anyone else found this differene and what was your solution? 
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Showing 5 responses by cleeds

helomech
If you want utmost accuracy, believe it or not, the best protractors are free.
I couldn't disagree more, and have long thought the cause of many complaints about LP playback are rooted in improper setup.

The Achilles Heal of most alignment gauges is that they align the phono cartridge, when the real goal should be to align the stylus/cantilever assembly. To do that precisely requires a mirrored gauge, such as the WallyTractor or Mint gauges.
fsellet
If you print an arc protractor on photo paper, it will give you the same precision as the Mint, minus the mirror for azimuth.

This is mistaken, and shows you don't really understand the basics of phono cartridge setup.

The value of the mirror isn't so much for azimuth - although it's useful for that - but aligning the cantilever for tangency. There's no way to do that with a paper protractor.
melm
When you wrote, "This is why Mint protractors are made one by one for each tonearm." it seemed you were ascribing greater precision to them, which would be incorrect. IMO the arc protractor, which was introduced originally by Wally Malewicz, as a marketing effort by him to make vinylphiles believe that they needed a custom, hand made and expensive device to do what the one-size-fits-all devices had been doing successfully for years. It worked ...
It worked, to a point. The accuracy of a one-size-fits-all protractor hinges in part on how precisely it can locate the arm pivot. That precision is iffy and varies depending on the gauge and the arm. A dedicated gauge doesn’t suffer that problem.

With just a little care the simpler ones, like my Cart-a-line or the turntablebasics an do the job just as well for a hobbyist ..
The Cart-Align gauge is particularly imprecise in locating the arm pivot.
jls001
And regarding mirrored surface for aligning the cantilever, use any small mirror.
That won't work. You'll need a mirrored gauge that includes an etched line that's used - along with the reflection of the cantilever - to achieve proper orientation of the cartridge in the headshell. That's how you can ensure tangency at the designated overhang point. Even with a pickup arm that doesn't specifically allow for adjustment of the cartridge at the headshell, there's enough potential left-to-right "slop" that not getting the cantilever aligned almost guarantees you'll never achieve tangency - even at the null points.
jls001
Do you mean the OH must be measured only at a specific point?
Typically, you measure overhang at two points. But how can you be sure you've achieved tangency at either or both of those points? How can you be sure the phono cartridge isn't twisted so as to not be tangent at the null points? You can do that by using a mirrored gauge that aligns the reflection of the cantilever with an etched line on the gauge that bisects the length of the cantilever.