Best DAC for $500

Just starting assembling my HIFI system.

Speakers - Snell Type D's - Biwired
Amp - Sunfire 2 Channel
Pre Amp - Parasound

Almost all of my music, 20,000 plus songs, is on my PC. Listen to my music either via I Tunes or Windows Media Player.PC does NOT have an upgraded sound card.

Very diverse music listening, from Rap, to classical, to metal.

Trying to determine if my best move is an external DAC,and if so the best for my current set up. Or an upgrade at sound card.

Help appreciated
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Elizabeth - have you heard the Arcam rDAC the Teddy Pardo PSU ? If not, I would strongly encourage you to do so. You may be surprised.
I agree with Elizabeth for the most part. I'd suggest trying out the Schiit Bifrost. There's a 15 day money back return policy, so if you don't like it, you're just out the shipping costs. The cost of the unit is ~$450 with the USB input. The DAC and USB cards are upgradeable, so if they come out with a new chip or USB 4 or something, you'll be able to upgrade without paying for everything else in the component. If I didn't already own an integrated Peachtree, I'd probably be trying one myself.
First off,thank you all for your responses.

Second, the back and forth (which I love) is part of the reason it takes me forever to finally buy something! For every good review there is a bad one.

Ultimately I know it comes down to what sound I like, just a bit difficult to grasp starting out!

Here is another piece of info that may help you help me.....

My song library, all 20,000 plus, has been accumulated over 10+ years. The source data is all over the place, original CD's, ITunes, Napster (yes that old), etc....

Whatever I get, needs to be able to handle all the various file formats.

And while I gave a $500 price point, if there is a big difference in sound level, I will gladly up the ante. There is a upgraded Mccormack that I was looking at...
I've tried a few dacs over the past while at different price points. Certainly they get better as you spend more, and the sweet spot seems to be around $1000-$1500.
For $500 I'd look for one that has very few features (i.e., no volume control/headphone amp) to ensure the money is spent on the DAC, not the features, faceplate and fancy knobs.

Two that offer good value are the Musical Fidelity V-DAC 2 (about $350) and the Simaudio Moon 100D ($600).

My 2 cents....