Whether you can hear it or not, bass does have texture (detail). So just whacking you in the chest doesnt mean the subs sounding as well as it could
Weve tested A Wilson Benesch Taurus which WHF claimed at the time to be the best sub on the market. We tried better cables and found more bass detail coming through
However, the WB is a top of the range sub. Many subs sound very poor to my ears so you might struggle telling any difference with yours
Personally speaking, I dont have a sub. I dislike them as they never seem to 'gel' with other speakers (even in the same range). But whenever ive upgraded speaker cables (as in properly upgrade, not just buying one willy nilly) the bass tends to be the biggest change in my system - deeper and more detail.
So in answer, it 'might' do for you. Id recommend a Van Damme UP LC-OFC interconnect to start with. If that makes no difference after a good run in then forget it
Depends on the length of cable. A 20m bootlace cable will carry the signal just fine but a properly shielded cable should deliver better results. A long balance cable should certainly sound superior to a long RCA but once again it depends on what you ar expecting from your system. If you want nightclub slam then a more accurate tight bass note may seem like a backwards step.
As with most things in this game listening for yourself is the only way to decide.