recommendation for speaker wire to soften the highs if possible


Hello,
I need help. My problem is my system sounds harsh on the highs to me. Not extremely bad, but enough that I need to fix it. My system consists of Ryan 610's, oppo Sonica Dac, and a Belles 150a hotrod amp. Speaker wires being used are old monster cable from the 90's. I also have monster cable rca. I mostly stream through Tidal. My question is can I make the desired effect by switching cables or should I add  a tube amp or pre amp. My budget on the wire would be around 300.00
Thanks in advance for any suggestions
128x128gunmetalzin
Lizzie, now that your system has matured, and you’ve added a lot of new wall plates and other stuff, do yourself a big favor and remove all ferrites from the system. Then listen. Even better put all the ferrites on appliance power cords, fridge, computer, TV, etc. Report back. 🤗
Post removed 
If you wish to just try new cables I suggest starting with interconnects not speaker cables, they are more important. After that speaker cables.
Post removed