Replace your stock power cords with thicker guage cords.
Replace any silver cables or stock cables with decent copper or gold ones.
If your cd player uses opamps, upgrade them or get one with a better analogue stage.
Replace the 701's with senn hd650's.
All these things can cause harshness/brightness in the highs. If you can find a oneac cb1112 on ebay for cheap, I recommend it for power conditioning.
Biggie.