Tube or R-2R DAC for Tube System

@bigkidz,
That sounds like a very fun listening experience. I know that you have several transports to choose from. Were you all using the Pro-Ject RS2 Transport?
Charles 

Actually just citing some successful  alternative examples that  DAC designers apply to avoid reliance on the ubiquitous OP-amp. My DAC I/V conversion is via a single passive resistor and has very  good sound quality in my opinion.  SW1X audio for example offers the choice of active transistor discrete or passive resistor with good outcomes from either option. I/V conversion has an influential role in determining sound quality that I believe is underappreciated by many.
Charles 

@itsjustme, 
 Some DAC designers prefer the sound and simplicity of a passive resistor and want to avoid the use of OP-amps due to what they consider to introduce sonic degrading NFB. I do recognize that another approach is active I/V conversion via a discrete circuit again avoiding OP-amps.

 I know that Audio Note utilizes transformers for I/V conversion duty. Given their reputation for very good sounding DACs I have to assume that the chosen transformers are of excellent quality. 
Charles 

@itsjustme,
Do you have any particular opinion regarding I/V conversion method, i.e. passive (resistor) versus active. Transistor vs transformer vs OP-amps?
Charles

@idolindian,
You were given excellent and wise advice from @verdantaudio. Don’t over generalize, implementation is more meaningful and worthy of consideration rather than strict R2R vs delta sigma dogma.

"I can show you warm, musical delta-sigmas and cold and bright R2Rs."
Truth!
Charles