For the budget conscious check out the Wolfson WM8740 USB DAC.
The following review is a year or two old but still relevant:
https://www.musicservertips.com/product-reviews/usb-dac-diy/
This little DAC is amazing for the price. I paid ~$50 and that included the power supply, I was able to order directly from the manufacture. eBay and Amazon charge a little more but still under $70 and you will get it delivered more quickly. This DAC has some limitations (only two input sources (USB and COAX) but for the money you can't go wrong.
The following review is a year or two old but still relevant:
https://www.musicservertips.com/product-reviews/usb-dac-diy/
This little DAC is amazing for the price. I paid ~$50 and that included the power supply, I was able to order directly from the manufacture. eBay and Amazon charge a little more but still under $70 and you will get it delivered more quickly. This DAC has some limitations (only two input sources (USB and COAX) but for the money you can't go wrong.