Which dac or other suggestions


First time poster here. I am looking for advice to increase the sound quality of my existing system. I have a Marantz SR7009 being used as a pre-amp powered by Emotiva's XPA-5, 2 revel m22 bookshelf speakers serving as my L & R, revel c52 center speakers and 2 revel timber matched C563 in ceiling rear surrounds. I mainly listen to music and switch between L &R stereo only and sometimes "all stereo" or matrix through all speakers. We do watch movies but seem happy with our home theater experience thus far although always open to suggestions. We mostly listen to music through a Sonos connect but we also do have an Orbit turntable. I know that the turntable will one day need to be upgraded to maybe a Rega RP3 or similar. I am in the process of adding two SVS SB12-nsd subs to the mix. Our room is large at 20x30x10 and I hope these subs will make some sort of impact. We also use an Apple TV. Now for my question.

I am looking to increase the sound quality of my Sonos driven music. I spoke to an audiophile (owner of Echo audio in Seattle) and he suggested a dac. In particular, because he knows I'm cheap haha!, he suggested the California Labs Sigma ii, Enlightened Audio Designs DSP-7000 mkiii, and some Krell dacs (stealth and ??) that I have never seen listed for sale. I missed an opportunity on both the Cal Labs and the EAD and I'm kicking myself. With ALL this being said, what other dacs should I consider? My budget is $750 or less and I would prefer $400 or less. Old vs new? Tube? NOS? DSD? Yadda yadda. I am looking for an increased sound stage and dynamic range. If I get more clarity and warmth then yee haw!

I appreciate all of your input in advance. Thanks for letting this first timer ramble.

Btw, I listen to mostly indie rock but I seriously dive into ALL types of music and yes I like it loud.
troydunnagan
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I would invest in a pre amp, because hooking an amp into the pre outs of an avr is not the route to go. pre outs on an avr are a after thought the avr job is digital first. some pre amps have pretty nice Dacs built in and have HT bypass. trust me you can get a pretty good pre amp in your price range and it'll make a huge improvement in sound quailty. Emotiva makes pre amps that will give you HT bypass and Parasound does as well but not sure how well Parasound would match up with your system? I wouldn't worry about cable, speakers or a DAC until you get a pre amp, this will give you the biggest improvement in sound quality at this point.
Save yourself a bunch of money and try one of the HiFiMeDIY ready made DACs.... the one below or one of their other models.

https://hifimediy.com/DACs/ready-made-dacs/9018-dac?sort=p.price&order=DESC

Same chip as the OPPO. <$100. If you don't hear a difference then no skin off your back.
Unless the 2nd Gen Vaults and Nodes have a better dac than the original, I would use an external dac. I have the original Gen 1 Vault and I love the controller app, but I think the dac ic terrible. 

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