Dac or Crossover

Hi All,
I own a very good system and wondering what would make the biggest improvement,a good DAC or upgading the crossovers on the speakers with Jensen capacitors ,kondo cables etc.
System - ART Noveau Speakers ,Mastersound 845 Mono Blocks,
Mastersound Ph5 Pre Amp ,Marantz Sa7 Cd player ,Isotek Sigma mains Condioner ,Kondo SPC Loudspeaker cables.
I don't know your CD player nor have any idea what DAC you are considering; but, something to think about:

If you are not happy with your CD player, upgraded speaker xovers will let you hear any problems it has that much better. My approach is usually to first upgrade as close to the source as possible. Good luck.
Is there an easy and well tested upgrade to the crossovers? It takes speaker designers some effort and time to "dial in" the right crossover. There are some widely accepted cross over mods for speakers like the Klipsch heritage series speakers but I have no lnowledge of A.R.T. speakers and even had a bit of difficulty looking them up.
DACs OTOH are widely discussed and there are opinions and preferences in many threads. I have none in mind but I am sure others will give you some guidance.
Hey, Patal! What kind of dac are you using now? Also, in response to your last response to me, I do agree there comes a point when you may want to just call it good and enjoy the music, and spend the money on more music. Happy listening!!