Pani,
That is indeed the purpose of the SB option. My suggestion as to tonearm weights assumed that your cartridge would have one. To my knowledge (and on my advice) the US distributor doesn't stock any ZYX cartridges without it (except perhaps the entry level Bloom). A ZYX without the SB would want an even heavier arm, like 22g+. Such arms are not common, and are almost unknown among today's designs.
***
In principle, I agree with Syntax agreeing with Dover. ;)
A tonearm faces a fearfully complex array of challenges and tasks.
The challenges include very precise motion management in an ever-changing and largely unpredictable, 3-D environment plus the management of randomly induced vibrations across the entire frequency spectrum.
Using only those highly chaotic inputs for guidance, the tonearm is tasked with holding the centerline of the cartridge precisely above the center of the groove (wherever it might be at any given moment) while maintaining a constant downward pressure. Good luck with that. It's like a 3-D tightrope walk on a constantly moving and jiggling rope. Oh, did I mention? The tightrope walker must keep his balance bar precisely perpendicular to the rope at every moment, even though the angle of the rope keeps changing... randomly!
Got all that? Now, whilst doing all the above the tonearm must also transmit the most delicate, low voltage signal your system ever sees, with no distortions, inaccuracies or induced changes of any kind. Good luck with that too.
A tonearm is the most difficult-to-engineer device in audio, which means it's the component best suited to screwing things up.
Put a great cartridge on a crap tonearm and you'll get crap, because most of the great things the cartridge drags out of the LP grooves will be damaged before they even reach your phono stage, if they reach it at all. Put an average cartridge on a great tonearm and you'll get fine music, because more of whatever the cartridge is capable of will reach the phono stage undamaged. This isn't empty theory. It's the explanation of what I've actually heard, many times. I've owned several crap tonearms, one decent tonearm and one really good tonearm and a bunch of cartridges. In every case, a good arm/cheap cartridge combo has stomped all over a cheap arm/good cartridge combo.
Among my analog toys I've got a $100 MM, a $100 vintage arm, a $4K LOMC and a $4K arm. Put the $100MM on the $4K arm and it sings and dances. It's a decent little cartridge and the arm lets it play its stuff. OTOH, put the $4K LOMC on the $100 arm and it shrieks and howls. The crappy arm just can't handle the tons of information from the highly revealing cartridge, so it produces disortions. Of course the best combo is the LOMC on the snazzy arm, obviously, but if I could only have one of those $4K components there's no question which I'd keep. The arm would stay.
