...the correct VTF in a given cartridge defines the correct position of the cantilever (= the coils in the magnetic field) towards the magnet(s) and that the correct SRA/VTA is always a matter of the position of the polished area of the stylus towards the grooved wall.
Dertonarm, your description is simple but precise!
Ortofon/OPUS3 have the highest required setting - i.e. the tonearm almost horizontal. Mercury SR is the deepest. About 14 mm down with the tail with a 10" tonearm.
Everything else (read: all other record companies LPs between 1958 and 1984) fall between these two extremes.
Dertonarm, according to these findings, do you imply in most cases the optimum range for a tonearm could be from perfect horizontal up to 14mm tail-down?
Most cartridge suspensions soften with age and use, so VTF needs to be reduced accordingly. When our current UNIverse was new it needed ~1.70g. Today (2+ years later) it plays optimally (better in fact) at ~1.20g. That is not a typo.
Doug, exactly! When my MY Sonic Lab Ultra Eminent BC was new, it sounded best at ~2.1g. After 1.5 yr until now, the best VTF is somewhere at 1.6-1.7g. Not all cartridges behave this way, though.
Dan