DAC upgrade

I was in the market for a high-end, reference caliber DAC about 4 years ago.  In order to maximize my buying power, I knew I wanted to buy pre-owned with a budget of about 5-7K.  I did my research and there were multiple choices to choose from on my list of possible audition.  However, it was impossible for me to get the opportunity to audition all the choices, at my home or, at the dealers.  Luckily, there were several dealers in my area that carried some of the same DACs I had on my audition list.  I auditioned several brands including DCS, Chord, MBL and others, but ultimately purchased Ayre Acoustic’s top-of-line Streaming DAC, as it was the best all-around performer for my money.  There are many excellent DACs on the market to choose from.  Listen to as many DACs as you can, and let your ears be your guide.  Happy listening.              

Well, the good news is at your budget you have plenty of options that’ll likely give you substantial improvements in terms of what you’re looking for, and obviously the hard part is figuring out which one to choose.  For what you’re looking for I’d look at Lampizator, Aries Cerat, or Audio Mirror Wave DAC (maybe a demo is possible for this one?) for tubes, and for solid state there’s Bricasti M21, Meitner, Totaldac, Berkeley, MSB, etc.  I’d start by reading reviews and whittling down which ones seem to offer most closely the characteristics you’re looking for, especially reviews that may compare to the DAVE or from reviewers who have previously reviewed DAVE, and go from there.  Hope there’s something of value here, and best of luck. 

I would love it if someone had direct comparison of the Aries Cerat Helene and the Audio Mirror Wave DAC's.

Don’t ruin a system like that adding room correction dsp.  Those devices degrade the signal quality greatly. Never heard one that didn’t. However if you did use REW and fixed your room acoustics that would be amazing. 
as far as dacs go, PLAYBACK MPD-8 seems to be the new go to for analog like sound with reference grade dimensionality.  Another option would be to try a Grimm mu2 which would potentially allow you to sell the Aurender. EMM labs has also been stirring the pot lately. I meet a lot of people buying used gear online and have talked to some fine seasoned high end audiophiles. One with similar tastes to me and has tried pretty much everything said his EMM labs DAC will never leave his side. There’s also the denafrips terminator + 15th. I’ve tried a lot of dacs and the terminator has been one of the most natural sounding and capable dacs. I had the esoteric N01XD SE and it was probably the most real and realistic sounding of the bunch but ultimately found it to be kind of bland musically.  In that price range I can’t offer much more than that unfortunately but might be something in there of value. Also you said you have great interconnects. May I ask what you’re using and if you have good power cords too?

I went from a Rockna Wavedream to a Lector s192 tube based dac. Couldn’t be further apart as far as comparing quality dacs are concerned. Rockna is super accurate with a strong attack. Saw deep into the recordings. Very real sounding. The Lector is very smooth and liquid. Connect with the music differently with both. With the Lector I just listen. The Rockna I tended to analyze the music more. Perhaps not quite as relaxing for me personally. I wouldn’t say that’s a negative for the Rockna and I would gladly own one again. I was selling equipment and was able to swap dacs and took the opportunity. I got to hear my system with each dac prior to having to decide. Wish I could own both. 
‘I’ve owned the Topping dl90, Cambridge cxn modified by ModWright with tubes and Audio Note dacs as well. The Rockna and Lector are at another level. The AN was unique and enjoyable as well. Good luck