Hi Jonathan,
For a start, please check out:
http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1235522919&openflup&128&4#128
You wrote:
"One thing that I haven't seen yet in these threads is an effort to _quantify_ the change in distortion that will occur if a cartridge is not precisely 9.52mm, what happens to the distortion if the base is shifted backwards (assuming an SME), how much the headshell offset angle needs to be changed to compensate, and how much slack you need between the headshell screwholes and mounting screws to accomplish the requisite change in offset angle. Cartridge alignment is never going to be perfect - for example a Baerwald alignment only results in zero tracking distortion at two tiny places over a span of 100mm or so. If we are going to talk about distortion, at least let us try to first quantify it, and then we can decide for ourselves if the level of distortion is acceptable or not."
If you define the amount of displacement, I'll gladly provide the measurements for the resulting changes: Null points, max. or specific distorsion for any r.
As you said, any alignment method worth considering will result in two Null points. The location of those will determine the distorsion magnitude at the error maxima.
In a previous post(different, but related thread) I asked what the threshold of tracing error related distorsions was(how far can we deviate from tangency before the distorsion becomes audible?). Off course there was no reply as this is largely dependent upon the individual(its tolerance to such distorsions) and the resolving power of the replay system.
What hasn't been addressed is the question whether different stylus profiles cause a difference in the magnitude and in the makeup(even/odd order harmonics) of those distorsions.
More specifically: Will a line contact stylus equipped cartridge produce less objectionable distorsions than, say, an otherwise identical one with a spherical stylus for the same alignment deviation from tangency in degrees and position on the record expressed as r ?
I realize that it makes limited sense only to produce identical cartridges with different stylii, when ideally a change of stylus profile requires other design changes(suspension etc.) as well.
Time to hit the sack...
All the best,
Frank Schröder
For a start, please check out:
http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1235522919&openflup&128&4#128
You wrote:
"One thing that I haven't seen yet in these threads is an effort to _quantify_ the change in distortion that will occur if a cartridge is not precisely 9.52mm, what happens to the distortion if the base is shifted backwards (assuming an SME), how much the headshell offset angle needs to be changed to compensate, and how much slack you need between the headshell screwholes and mounting screws to accomplish the requisite change in offset angle. Cartridge alignment is never going to be perfect - for example a Baerwald alignment only results in zero tracking distortion at two tiny places over a span of 100mm or so. If we are going to talk about distortion, at least let us try to first quantify it, and then we can decide for ourselves if the level of distortion is acceptable or not."
If you define the amount of displacement, I'll gladly provide the measurements for the resulting changes: Null points, max. or specific distorsion for any r.
As you said, any alignment method worth considering will result in two Null points. The location of those will determine the distorsion magnitude at the error maxima.
In a previous post(different, but related thread) I asked what the threshold of tracing error related distorsions was(how far can we deviate from tangency before the distorsion becomes audible?). Off course there was no reply as this is largely dependent upon the individual(its tolerance to such distorsions) and the resolving power of the replay system.
What hasn't been addressed is the question whether different stylus profiles cause a difference in the magnitude and in the makeup(even/odd order harmonics) of those distorsions.
More specifically: Will a line contact stylus equipped cartridge produce less objectionable distorsions than, say, an otherwise identical one with a spherical stylus for the same alignment deviation from tangency in degrees and position on the record expressed as r ?
I realize that it makes limited sense only to produce identical cartridges with different stylii, when ideally a change of stylus profile requires other design changes(suspension etc.) as well.
Time to hit the sack...
All the best,
Frank Schröder