Looking for some recommendations with the following need to haves and nice to haves... Need to haves... $500 budget cap Wired Circumaural design Comfortable with glasses Great isolation & as close to zero as possible sound leakage (I'm in an open office environment, that is occasionally noisy...

I need to connect a 1/8" stereo audio output to a 1/4" balanced input on a single KRK Rokit 5 studio monitor. My goal is to have the stereo channels merge to a single mono channel. Wondering if a standard 1/8" stereo to 1/4" stereo cable will achieve this goal, or if I'll run into any problems...