Hi Axel, well - usually I did not get very sympathic comments here whenever I refered to math/geometry in analog playback set-up.
Maths would tell the story here too, but I will put it in more general words:
- the heavy cartridge body does add to the effective mass of the moving system (tonearm + cartridge + generator - NOT stylus) in a very special way. The body mass of a heavy cartridge can - and will - alter the effective moving mass extremely. Thats why the "regular" calculations (middle-mass tonearm + medium to high compliance cartridge ) are all a sudden null and void. One of the reasons why so many audiophiles aren't thrilled with the sonic performance of the high-priced (and heavy....) stone-bodied Koetsu's.
These cartridges are almost impossible to mate well with ANY tonearm.
High compliance - low compliance - medium compliance - these are are results of special requirements in the design of a given cartridge. This has to do with interaction between magnetic force, suspension material, cantilever stiffness, moving mass of cantilever/stylus and several other factors.
Jonathan Carr could write you a 2 pages post about these.
Coming back to this topic here, - and to concentrate the output.... - the cartridge bodies weight has such a big influence (if of considerable mass) on the behaviour of the tonearm and on its effective moving mass, that it can make it impossible to mate a particular cartridge with ANY tonearm.
A stone-bodied Koetsu will perform well in a very few tonearms. In these tonearm it does so, because these arms do feature outstanding energy transfer abilities and are extreme stiff and rigid. But even in these tonearms it is still a missmatch because the combination of high compliance PLUS high body mass is a NO GO for any tonearm. (God, - the Koetsu-lovers will kill me..... hey there! I like Koetsu's too, but would always go for the RSP....).
IGD - has nothing to do with compliance or mass alone.
Usually you are better off, if your cartridge is a good "tracker".
IGD can most likely be avoided, if your alignment goes for the 2 zero widely spread and the 2nd close to the run-out grooves.
IGD is a question of geometry and trackability. Many high compliance MMs do feature extreme trackability - but this alone does not mean low IGD.
Align a Shure V15VMR with IEC-geometry and play a DECCA SXL with Ravel Daphnis & Chloe conducted by Monteux:
You will get IGD even with the 100µm+ trackability of the Shure.
Because your Shure's stylus will already be close to its maximum error with the big crecsendi on the sides end.
An ultra hard 5-6 compliance FR-7 will easily go through those inner grooves without any distortion if mounted in a FR-60-series and aligned with a Denessen tractor.
Greetings,
Daniel
Maths would tell the story here too, but I will put it in more general words:
- the heavy cartridge body does add to the effective mass of the moving system (tonearm + cartridge + generator - NOT stylus) in a very special way. The body mass of a heavy cartridge can - and will - alter the effective moving mass extremely. Thats why the "regular" calculations (middle-mass tonearm + medium to high compliance cartridge ) are all a sudden null and void. One of the reasons why so many audiophiles aren't thrilled with the sonic performance of the high-priced (and heavy....) stone-bodied Koetsu's.
These cartridges are almost impossible to mate well with ANY tonearm.
High compliance - low compliance - medium compliance - these are are results of special requirements in the design of a given cartridge. This has to do with interaction between magnetic force, suspension material, cantilever stiffness, moving mass of cantilever/stylus and several other factors.
Jonathan Carr could write you a 2 pages post about these.
Coming back to this topic here, - and to concentrate the output.... - the cartridge bodies weight has such a big influence (if of considerable mass) on the behaviour of the tonearm and on its effective moving mass, that it can make it impossible to mate a particular cartridge with ANY tonearm.
A stone-bodied Koetsu will perform well in a very few tonearms. In these tonearm it does so, because these arms do feature outstanding energy transfer abilities and are extreme stiff and rigid. But even in these tonearms it is still a missmatch because the combination of high compliance PLUS high body mass is a NO GO for any tonearm. (God, - the Koetsu-lovers will kill me..... hey there! I like Koetsu's too, but would always go for the RSP....).
IGD - has nothing to do with compliance or mass alone.
Usually you are better off, if your cartridge is a good "tracker".
IGD can most likely be avoided, if your alignment goes for the 2 zero widely spread and the 2nd close to the run-out grooves.
IGD is a question of geometry and trackability. Many high compliance MMs do feature extreme trackability - but this alone does not mean low IGD.
Align a Shure V15VMR with IEC-geometry and play a DECCA SXL with Ravel Daphnis & Chloe conducted by Monteux:
You will get IGD even with the 100µm+ trackability of the Shure.
Because your Shure's stylus will already be close to its maximum error with the big crecsendi on the sides end.
An ultra hard 5-6 compliance FR-7 will easily go through those inner grooves without any distortion if mounted in a FR-60-series and aligned with a Denessen tractor.
Greetings,
Daniel