Newbie Needs Help

I have a Bal Canto Evo 2i, a Cary 303/200 and JM Lab Chorus S speakers. I know my speakers are the weak link but I don't have the wallet for a substantial upgrade at this point in time.

I like the bass and mid that I get from the setup but the highs are a little too harsh and bright. I'm using a very old set of MIT 750 S3 speaker cables and stock power cords. I do not have a power conditioner.

Does anyone have any recommendations for cables or power options that may relieve the harshness that I'm getting from the top end, without adding to what I already think are quality mids and lows?

Thanks for any suggestions,
Try copper cables. This may sound strange but just go down to a Home Depot or a like store and purchase solid copper cable in a thickness that reflects the power or current of your amp, twist the single wires together using about 2 twists per inch,less for thick wire, to bind the pair. Try them out. If you dont like them you can pitch them with a nominal loss. If you like them then try the "Clear Sound" coppers with the copper terminations, I think they advertise them on Audiogon. Or keep them and use a good copper termination.
Please let us know which interconnects you're using between the Cary and the Bel Canto.
Two words: Room Treatment.
$ave the $ for room treatment or new spkrs.
I'm just using some cheap monster cables right now as interconnects. Forgot to mention that I was looking for recommendations for those as well.