Help with first cable upgrade.


I have a Musical Fidelity v-150, rotel rp-3000 turntable and an old Sony CD player.  I have 2 sets of speakers B&W CM2's and JM Lab chorus floorstanding speakers I may have to part with due to space.  My power cables and interconnect cables are cheap stock.  My speaker cables are a 20 year old or so set of MIT shotgun cables.  Any recommendations for budget friendly cables that may help the bass or soften the brightness of my system?  Thanks.
shimanole
You might consider these for interconnects:
https://stagersound.com/silver/Amazingly good, transparent and uncolored.As for your Sony CD player: weak link,but if the transport is good, (and it has a digital output) a decent outboard DAC will make an enormous improvement.
Performance Audio is the cheapest on Canare 4s11 bi-wire speaker wire I've seen at $1.16 a foot with free shipping UPS with a $20 purchase, don't know how they can do that and make a profit. 

If your speakers are a little bright put some felt double taped around your tweeters. Cymbal felt for cymbal stands from a drum shop work well cut into 4 pieces, may look funky but can break up aggressive beaming  highs and it's cheap.