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I haven't gone through and read all the posts so I might have missed some similar thoughts and sounding repetitive. In theory a linear tracker simulate the tangency of the record cutter but one must remember a cutter is an ACTIVE device, it forces a straight line across the record in order to cut a record but a linear tracking arm is a PASSIVE device that is tracking in the mercy of the record groove with its angles and turns! In real world tracking, most center holes on records are not absolutely centered, very often few millimeters off! Bam, there goes tangency out the window.
As one commenter points out tangency is based on the cantilever - shape of the stylus tip too if you want to be anal about it - in relation to the groove NOT the arm. Bear in mind the cantilever is attached to rubber, hence a compliant system! So imagine the cantilever is constantly navigating with side force of the off center record thrusting it laterally banging on left and right and you tell me if that's perfect tangency or not! Of course the perfect table for a linear tracking arm to work on would be something like the Nakamichi Dragon or TX1000 that self corrects off center record hole but how many people have a table like that?
I think the reason people prefer the sound of linear tracker over pivot arm is that tracking error is still lower than many pivot arms, especially the shorter one that's not optimized in overhang and anti-skating adjustment. I don't have problem with people preferring linear tracker over pivot but just don't be so militant about it and keep insist on telling me linear trackers have perfect tangency! It does not! It's still a compromise and so is life. To me all the fiddling is distracting me from playing record but your mileage may vary of course.
I mean, just think about it, a stylus is attached to a cantilever and then attached to rubber and then attach to an arm and then attach to a counterweight all the way at the end and you expect the geometry to be perfectly tangent through out playing one side of a record for 20 minutes straight? We know how dramatic the overhang is off by one millimeter can sound with pivot arms so imagine a record with a one millimeter off-centered hole, not uncommon, played with a linear tracker. Perfect tangency? NOT!
Anyway, I used to have problem with servo pseuso-linear tracking arms because the obvious objection to the constant self correcting nature of its design but crabbing across the record with tiny arcs but I have since come to appreciate it more because it's much less stressful on the cantilever and stylus and navigate the groove much easier in REAL WORLD situation. It's really a pivot arm with a uni-directional gliding base, if that helps the mental picture. (uni-direction in typical designs not counting Pioneer's PL-L1000 bi-directional arm) The problem with the sound of many servo design is not the concept but the execution and many don't use good bearings and if look at it as a pivot arm it's no where near the quality of top notch arms like the Graham, Triaplanar, SME V, etc... I have a Yamaha PX-2 and it works wonderfully and it's better than many servo arm in its mechanical quality. Of course not in the league of top notch pivot arms but the lessening of tracking error (not perfect tangency) does pay dividend. So I hope in the future, someone can design a "servo tonearm mounting base" that allows one to mount any pivot arm that can servo control the base's lateral movement to lessen tracking distortion (lessen not eliminate) Wouldn't that be something cool? Hell, if I mount a 12" arm on such device the tracking error would be so low to not even worry about such a thing!
I forgot the mention another solution such as the Thales arm that is a combination of pivot and linear tracker by self adjust to tangency in a PASSIVE system. Very clever indeed. But the only problem I can think of is that by adding another pivot right above the cartridge might affect the structural integral of the arm and having extra linkage might hinder its fluid movement. Again, nothing is perfect but I can at least appreciate the innovation. Bravo!
Speaking of 12", I honestly thing a 12" arm makes sense unless you are in the rigidity is everything crowd. There's no perfect arm and I can accept that just like life and a well desing 12" seems to be a good compromise.
At the end of the day, I just want to play some tunes and not worry about whether the damn needle is tangent or not. That's it for now.
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I haven't gone through and read all the posts so I might have missed some similar thoughts and sounding repetitive. In theory a linear tracker simulate the tangency of the record cutter but one must remember a cutter is an ACTIVE device, it forces a straight line across the record in order to cut a record but a linear tracking arm is a PASSIVE device that is tracking in the mercy of the record groove with its angles and turns! In real world tracking, most center holes on records are not absolutely centered, very often few millimeters off! Bam, there goes tangency out the window.
As one commenter points out tangency is based on the cantilever - shape of the stylus tip too if you want to be anal about it - in relation to the groove NOT the arm. Bear in mind the cantilever is attached to rubber, hence a compliant system! So imagine the cantilever is constantly navigating with side force of the off center record thrusting it laterally banging on left and right and you tell me if that's perfect tangency or not! Of course the perfect table for a linear tracking arm to work on would be something like the Nakamichi Dragon or TX1000 that self corrects off center record hole but how many people have a table like that?
I think the reason people prefer the sound of linear tracker over pivot arm is that tracking error is still lower than many pivot arms, especially the shorter one that's not optimized in overhang and anti-skating adjustment. I don't have problem with people preferring linear tracker over pivot but just don't be so militant about it and keep insist on telling me linear trackers have perfect tangency! It does not! It's still a compromise and so is life. To me all the fiddling is distracting me from playing record but your mileage may vary of course.
I mean, just think about it, a stylus is attached to a cantilever and then attached to rubber and then attach to an arm and then attach to a counterweight all the way at the end and you expect the geometry to be perfectly tangent through out playing one side of a record for 20 minutes straight? We know how dramatic the overhang is off by one millimeter can sound with pivot arms so imagine a record with a one millimeter off-centered hole, not uncommon, played with a linear tracker. Perfect tangency? NOT!
Anyway, I used to have problem with servo pseuso-linear tracking arms because the obvious objection to the constant self correcting nature of its design but crabbing across the record with tiny arcs but I have since come to appreciate it more because it's much less stressful on the cantilever and stylus and navigate the groove much easier in REAL WORLD situation. It's really a pivot arm with a uni-directional gliding base, if that helps the mental picture. (uni-direction in typical designs not counting Pioneer's PL-L1000 bi-directional arm) The problem with the sound of many servo design is not the concept but the execution and many don't use good bearings and if look at it as a pivot arm it's no where near the quality of top notch arms like the Graham, Triaplanar, SME V, etc... I have a Yamaha PX-2 and it works wonderfully and it's better than many servo arm in its mechanical quality. Of course not in the league of top notch pivot arms but the lessening of tracking error (not perfect tangency) does pay dividend. So I hope in the future, someone can design a "servo tonearm mounting base" that allows one to mount any pivot arm that can servo control the base's lateral movement to lessen tracking distortion (lessen not eliminate) Wouldn't that be something cool? Hell, if I mount a 12" arm on such device the tracking error would be so low to not even worry about such a thing!
I forgot the mention another solution such as the Thales arm that is a combination of pivot and linear tracker by self adjust to tangency in a PASSIVE system. Very clever indeed. But the only problem I can think of is that by adding another pivot right above the cartridge might affect the structural integral of the arm and having extra linkage might hinder its fluid movement. Again, nothing is perfect but I can at least appreciate the innovation. Bravo!
Speaking of 12", I honestly thing a 12" arm makes sense unless you are in the rigidity is everything crowd. There's no perfect arm and I can accept that just like life and a well desing 12" seems to be a good compromise.
At the end of the day, I just want to play some tunes and not worry about whether the damn needle is tangent or not. That's it for now.
___________________