There is a reason the OP likes the bell wire: Single strand copper conductors in a. thin sleeve - usually PVC, but can sometimes be found with the much preferred polyethylene sleeve. It’s cheep and in short runs, does a great job at transmitting an audio signal without adding any character of it’s own.
My favorite speaker cable/wire by far, regardless of price, is of the same principal only made with somewhat better materials and a little more engineering: single strand, 24 AWG,. OCC copper in a thin PTFE sleeve, with both leads helical wound and sheathed in a light, natural fiber, woven jacket. Not really cheep at about $1,200.00 for a 8’ bi-wired pair - still the best and most neutral I’ve found for my system regardless of price.
My point is - if you haven’t tried bell wire, give it a shot. If you don’t like what you hear, maybe the problem is somewhere else in your system......Jim