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
gunmetalzin
I reccomend Cardas,they do a great job of warming up a system and subtly rolling of highs. I dont recommend them for tube equipment though.
I certainly agree about Cardas, I tried that for my DAC before switching over to the isolation transformer. It was an improvement, but it was a bandaid not a fix.
I love reading the responses to these sorts of questions. Every answer a different notion. Try this try that, no it's your frammims.. Sorry you need a new _______. (twenty different things)If you do them all, you would have spent the equivalent of a down payment on a new home. And still have no answer. The pitfalls of audio madness.