Dear Axelwahl,
I will keep it as short as possible.
1) it is possible to adjust teh overhang by moving the whole tonearm. But if you do so, your specified mounting distance is gone unless you move your tonearm on a circle segment always amintaining the very same spindle-bearing distance. This is a simple geometric fact. A sheet of paper and a pair of dividers will nicely illustrate the point.
2) The geometry depends on the mounting distance of the tonearm as the first NON-variable parameter of the basic calculation. If you adjust the overhang (which depends on the spindle-bearing distance founded geometry...) by altering the basic parameter, the overhang you just adjusted to is no longer the overhang you tried to align to..... because you moved the tonearm.....
3) the overhang DEPENDS on the mounting distance - not vice versa....
4) It is a BIG difference, whether you adjust the overhang with oblonged holes in the headshell (because the mounting distance remains, as you do not move the tonearm.... only the stylus) or by moving the tonearm. To adjust the overhang is a movement RELATIVE to the FIXED tonearm. You move the stylus relative to the bearing pivot and the spindle - not the tonearm!!
The spindle and the pivot bearing are FIXED PARAMETERS because their distance is the FOUNDATION of your tonearms geometry.
You can choose different zero-error points on the arc of the tonearm/stylus movement over the LP's surface and by doing so you can - for instance - bring the 2nd zero-error point closer to the inner grooves.
However - the basic geometry of your tonearm remains the same.
The nice alignment tool provided with every Graham tonearm gives a nice idea. You can align your cartridge to either Loefgren or Baerwald geometry, but you do so without moving the Grahams base - you align at the headshell only.........
The groove modulations in any LP are VERY small. A "bit" derivation results in HUGE errors in de-modulating because the VERY TINY polished areas of your stylus are no longer aligned.
Thats the difference in playback between distortion-free High-end and "so so" sound with inner groove distortion.
1-2 mm........ well, your polished flanks on the stylus are 2-8 µm (thats 1000th of a millimeter).....
1-2 mm here are 10 - 20 miles in real world playback.
So - in metapher, you are "still in the same county or district, but you are no longer in the same block, you are in a different part of the city - and you will never find the address the Lady gave you to meet her...."
In analog playback all quality starts here - at the demodulation in the grooves of the LP. If you do not precisely align 100% here - you will have an endless (and futile...) journey trying to fix problems in your system which you never can locate or solve.
I will keep it as short as possible.
1) it is possible to adjust teh overhang by moving the whole tonearm. But if you do so, your specified mounting distance is gone unless you move your tonearm on a circle segment always amintaining the very same spindle-bearing distance. This is a simple geometric fact. A sheet of paper and a pair of dividers will nicely illustrate the point.
2) The geometry depends on the mounting distance of the tonearm as the first NON-variable parameter of the basic calculation. If you adjust the overhang (which depends on the spindle-bearing distance founded geometry...) by altering the basic parameter, the overhang you just adjusted to is no longer the overhang you tried to align to..... because you moved the tonearm.....
3) the overhang DEPENDS on the mounting distance - not vice versa....
4) It is a BIG difference, whether you adjust the overhang with oblonged holes in the headshell (because the mounting distance remains, as you do not move the tonearm.... only the stylus) or by moving the tonearm. To adjust the overhang is a movement RELATIVE to the FIXED tonearm. You move the stylus relative to the bearing pivot and the spindle - not the tonearm!!
The spindle and the pivot bearing are FIXED PARAMETERS because their distance is the FOUNDATION of your tonearms geometry.
You can choose different zero-error points on the arc of the tonearm/stylus movement over the LP's surface and by doing so you can - for instance - bring the 2nd zero-error point closer to the inner grooves.
However - the basic geometry of your tonearm remains the same.
The nice alignment tool provided with every Graham tonearm gives a nice idea. You can align your cartridge to either Loefgren or Baerwald geometry, but you do so without moving the Grahams base - you align at the headshell only.........
The groove modulations in any LP are VERY small. A "bit" derivation results in HUGE errors in de-modulating because the VERY TINY polished areas of your stylus are no longer aligned.
Thats the difference in playback between distortion-free High-end and "so so" sound with inner groove distortion.
1-2 mm........ well, your polished flanks on the stylus are 2-8 µm (thats 1000th of a millimeter).....
1-2 mm here are 10 - 20 miles in real world playback.
So - in metapher, you are "still in the same county or district, but you are no longer in the same block, you are in a different part of the city - and you will never find the address the Lady gave you to meet her...."
In analog playback all quality starts here - at the demodulation in the grooves of the LP. If you do not precisely align 100% here - you will have an endless (and futile...) journey trying to fix problems in your system which you never can locate or solve.