Alright! What is the difference between the Lyr 3 and built-in DAC vs. the normal one paired with a Bitfrost?

I’m not using it for virtual surround sound (not a huge fan of it) but it does have a toslink output/input. I’d prefer to get rid of the sound card and give it to my little brother to use on his computer but it’s not a big deal. What are the main differences between the LCD-2C and the LCD-X or...

EDIT: Changed to post below

So this is my first post and hopefully it’s okay and all the information you need is here. I currently have a DT770 Pro with an internal sound card but I’m wanting to purchase an Amp, Headphone, and a DAC with a budget of roughly $2000 to have an actual setup. I’d like to try a tube amp out but...