How is SQ affected by compliance of the cantilever. Curious to know.
Thanks,
Good question!
Honestly I don't know the answer.
Some parameters that affect how a cartridge sounds:
1/ moving mass (stylus + cantilever), typically the best cartridges have about 0.5 mg or less. One great technique employed by cartridge makers is to use the most lightweight yet most rigid material as cantilever material. Boron and beryllium come to mind (like the Audio Technica AT ML170 which had boron cantilever). But both metals were toxic for workers so they're no longer used. Diamond is the most rigid but since it's very dense there is weight penalty, hence they were usually very short (like Dynavector 13D or 17D). Sapphire and ruby cantilevers are popular too even today but they're way less rigid than diamond while still having weight penalty of a semi precious stone. Aluminium isn't the best but it's sufficiently rigid, lightweight and cheapest. There were titanium and carbon fiber cantilevers too. A great trick used by cartridge makers to reduce weight further was to taper the cantilever. Check out pictures of Astatic MF100 or Empire 4000D/III. They're both beauties.
2/ the geometry of the stylus: the cheapest cartridges typically have conical stylus. The chain goes up with elliptical diamonds. Beyond that are the various specialty shapes that usually have trademarked names like Shibata, Microline, octahedral, hyper elliptical, Gyger, Line Contact, Vital, etc. These specialty styli are more demanding of correct setup compared to conical or regular elliptical but by virtue of their shapes they also bring out more details from the groove. One of the reasons why such special shapes had to be developed was the introduction of CD4 standard which allowed quadrophonic channel playback. The stylus must be capable of reproducing at least till 30000 Hz because the rear channels were carried on carriers above audio band. IIRC, it was JVC and others who developed the stylus.
3/ cartridge resonance: most MM cartridges have a self resonance within the audio band. Some as low as 8-10 kHz, but more commonly >12-14 kHz. This messes the frequency response at least one octave above and below the resonance frequency. This is the reason why we use a capacitor load at the input of the phono preamp to try and shift the resonance frequency to a desirable frequency. The resistor in parallel fine tunes the amplitude of the resonance. Besides, the resonance also results in phase shift. So often MM cartridges have a rising response which peaks near 20 kHz. One way of pushing this frequency above 20 kHz is to have the lowest possible cartridge coil inductance because the resonance frequency is a direct function of the inductance value. The con of this is that the lesser number of coil windings results in lower output voltage. Most MCs have extremely low inductance compared to MMs so their resonance frequency is typically well beyond 20 kHz (and hence do not need the aid of a capacitor loading like MMs do). A good in-between implementation is moving flux cartridges as they have much lower inductance compared to typical MMs.
There are other lesser determinants too, like strength of the magnet used, quality of winding (like the use of PCOCC copper windings), how damped is the cartridge body (plastic versus cast metal body), etc.
Higher compliance cartridges will trace better than lower ones. Better tracing of the groove results in a more planted reproduction. Most cartridges fail woefully to trace 'trick' records like the cannon shots on Tchaikovsky 1812 Overture but such records are more the exception than the norm. I think if a cartridge can trace 80 micron grooves it will trace most music. 90 microns would be outstanding.
IMHO, of course.
