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
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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I've been away from big living room systems for quite awhile (ie, tube preamps, amps, subs/speakers). It has been all desktop audio for me over the past decade.

I've owned 4 DACs for the desktop. Never heard any big-bucks audiophile approved models so can't comment. However, I can tell you that I have not found all DACs to sound alike (not even close).

My appreciation of digital audio was revolutionized 1 year ago when I took the plunge & bought an Audio GD NOS 19 (the non-oversampling version of their popular DAC-19 R2 R design). What a difference! Most of the differences come in tonality/rendition of audio frequencies, rather than soundstaging (w/o a big, bad L.R. audio system, it's harder for me to evaluate soundstaging).

The NOS 19 is by far the least digital DAC I've ever heard. While not sounding exactly like analog (T.T. or tape), it also sounds nothing like any delta-sigma DAC I've heard. No more tizzy/anxiety-producing glare in upper midrange & treble; no more dry-as-a-bone bass (deep, hitting hard, but dry).

The NOS 19 sounds organic, relaxed, spacious, tonally rich. Either through quality headphones or my powered desktop monitors (modded Yamaha HS7s + SVS SB1000 sub), I cannot detect any frequency emphasis at all. Some say it's rolled off in the upper treble. I'm not sure about that.

Beyond having a non-tizzy treble, the NOS 19 has a very pleasing fullness to notes (all frequencies). The bass is very nice, indeed; it has been called "wet" (opposite of dry), and I would agree with that. More to the point, cellos or a jazz string bass sound totally like real instruments. Bass notes launch, then decay in a most natural way.

The NOS 19 so impressed me that I purchased on of the last of the non-oversampling DAC-19s (it has been superceded by a different Audio GD R2 R model). The DAC-19 is also quite impressive IMO, again, sounding little like any delta-sigma DAC. I find it lacks that last bit of fullness & organic sound, but had I not heard the NOS 19, the DAC-19 would be far and away my favorite DAC.

You can find a used DAC-19 online for ~$600. You should look for one from 2016 onward. I used HiFiShark.com for these searches. Here is their result from a DAC-19 search:
https://www.hifishark.com/search?q=Audio+GD+DAC-19

(the audiocircle listing looks pretty decent to me)

It's unusual to find a NOS 19 F.S., though they do come up every now and then.