What makes a DAC so expensive?

The complexity of the build ,the power supplies, are essential in the S/N  and purity of signal, many aftermarket linear power supplies are over $1500 alone ,brand name , how fancy the case 
If a R2R multi ladder dac each resistor has be matched to possibly hundreds of resistors ,clock ovens all kinds of add o to empty your wallet DCS dacs with all maxed out power supplies ,and super clocks $90k combo, the best sounding digital on the planet 
that can rival the best of Anything out there, but Slightly out of my budget !!

Those that don’t want to spend the money justify having not done so.

Those that have spent the money justify having done so. 
And so the wheel turns, and turns, and turns. To me it comes down to what camp your ears tell you your in. 
I went from a Bluesound Node 2i to a separate Audio Mirror DAC followed by replacing the Node completely with the addition of a LUMIN Streamer. Both phases of the transition were substantial but heavily weighted towards adding the separate DAC. No comparison.

@mvrooman1256

curious if you went from node 2i to lumin while you had your audio mirror dac already... if so:

- any perceivable sq improvement in going bs --> lumin?
- what connection used?
- what speakers and amps in system?

presuming you used node 2i bnc digital out... not its poor onboard dac

many thanks

@jjss49  I started out with Schitt Vidar monoblocks and a Schitt Freya+ preamps with a Node 2I functioning as my DAC and streamer.  Speakers are Magnepan 1.7i’s.  I added the Audio Mirror DAC and continued to use the Node 2i with an coax cable as a streamer only.  The difference was substantial and obvious.  Way less harsh, bigger sound stage and things just seemed to open up.  A lot more space to the music.  I then added the LUMIN streamer and completely removed the Node from the chain.  A difference but not as big as switching to an outboard DAC. 

@mvrooman1526 

i am only asking specifically about the perceived sq difference from the streamer swap from node 2i to lumin - both feeding the same audio mirror dac

you are saying there WAS a difference, but very small, correct?  what was the difference?