lewm, first of all, all we are trying to do is set a tangent at two different radii. It is not brain surgery. 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, and when Wally couldn’t/wouldn’t deliver consistently, Mint stepped in.
And in case YOU don’t know it, the SMARTractor and the UNItractor.are copies of the original Dennison Geometric Soundtractor which had been around at the dawn of the stereo era. Either the patent has run out or was purchased/licensed
I cannot imagine anyone spending $600 for such a device unless, perhaps, if they do TT set-ups professionally (and write off the expense). 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.. IMO, though, a mirrored protractor is a must as one should be aligning the cantilever and the mirror forces you to get that right.
I often think there’s too much emphasis on HTA anyway. One successful pivoted TT arm even avoids that totally. Some people think accuracy in azimuth and SRA are far more important. And anyone who wants to spend unnecessary big bucks on devices to adjust these will also find willing purveyors.
And in case YOU don’t know it, the SMARTractor and the UNItractor.are copies of the original Dennison Geometric Soundtractor which had been around at the dawn of the stereo era. Either the patent has run out or was purchased/licensed
I cannot imagine anyone spending $600 for such a device unless, perhaps, if they do TT set-ups professionally (and write off the expense). 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.. IMO, though, a mirrored protractor is a must as one should be aligning the cantilever and the mirror forces you to get that right.
I often think there’s too much emphasis on HTA anyway. One successful pivoted TT arm even avoids that totally. Some people think accuracy in azimuth and SRA are far more important. And anyone who wants to spend unnecessary big bucks on devices to adjust these will also find willing purveyors.