Upgrading to a stand alone DAC

I’d think either the Gustard R26 or the new Denafrips Ares 15th would be a meaningful improvement in all areas.  Best of luck. 

There are a few used Denafrips Pontus II 12th units for sale at the moment.  They all are in your price range and would give you what you are looking for.  You can add the Iris or Hermes DDC later as well which uses the I2S input and increases resolution, soundstage and imaging.

Denafrips R2R DACs are hard to beat for the price.

Forgot to mention, don’t discount the importance of a digital cable and choose with care as it can make a big difference in how much you get out of a DAC. 

If you can find one used, the Denifrips Pontus ll should be in your price range. Over the last few years, I’ve upgraded everything in my system, except my Pontus ll.  Maybe some day, but I’m in no hurry.

All the best.