I'm looking for a pair of interconnects that won't shatter the bank....

I use SKW RCA cables, available on amazon. They provide a noticeable improvement over cheapo cables and won't break the bank. The sound improvement in the connection between my CD player and preamp was actually shocking.

Why do people consistently ask for help and only give partial details instead of all the information needed to properly  answer the question? A cheap cable to me is $600😂

@tom6897 Right? Details are actually helpful. 
As mentioned above, interconnects to the sub make little difference. So many other cable possibilities. None of us can give you any sort truly meaningful advice though without more details.

A little over eight years ago I came across a very positive review of Stager cables in Audiocgon:https://forum.audiogon.com/discussions/stager-silver-solid-interconnects-2.htmlBased on that and other reviews and user comments on the Silver Solids website, I decided to try a one meter pair, given that I could return it for a fill refund if I wasn't satisfied.Long story short: They're exceptional cables, among the finest available probably at any price. My entire system is uses Stagers, and some friends who share my love of music, live and well reproduced, also have them and are very happy with them. And they are not as expensive as you'd expect for this level of excellence. (I just checked and the prices are still the same as when I bought them in 2013.)
It would be advisable to use best the best cables for all your runs, being that they will be in series from preamp to subwoofer and back to your amplifiers. But if you can run the subwoofer independently and just use silver interconnects to you amplifiers, with splitters at the preamp, then the quality of the subwoofer cables will not be as important. But then you would be running the stereo speakers full range and the subs just for some additional low end boost.

There are some amazingly good cables available on Amazon for a fraction of the advertised brands.  Like 10% of their cost. Next rung up I'd have to go with Pangaea. I got a a set of their TT cables and am very pleased for under $100.  Beyond that, your wallet is the limit.