Downside to R2R Ladder DACs?

@abraxalito, think I have some of them laying around, do you know if they're unity gain stable, no mention in the data sheet.

Cheers George
 

@georgehifi Its not a drop-in for normal opamps because its CFB. I get better results using a passive filter before my opamps than I did with AD811 and no filter. AD829 is doing very nicely as I/V for me at present, preceded by a filter.

...steer clear of used R2R DACs, since their reliance on high precision resistors causes them to sound best when new, and degrade fairly quickly...

I think your sales person is trying to sell you a new DAC.

My R2R DAC is a Theta ProBasic III that is more than 20 years old. I love the thing as it does it does not have that treble edge that one hears in so many "modern day" DACs.

Listed new for $2,700 and I bought used about three years ago for $600.

Thanks for listening,

Dsper

At therisk of being contentious: Aggressive treble is more a sign of poor clocking than a design fault of delta sigma dacs compared to r2r dacs. Even highend dacs benefit from reclocking with Mutec, Cybershaft, Antelope, sotm et al. There is no superiority in r2r dacs, they tend to be more euphonic but sometimes less resolving. YMMV