You have a fairly wide choice of chipsets. Latest generation of 24-bit DAC chips are all Delta-Sigma designs, with PCM1792, AD1955, and SM5865C being top-spec models from Burr-Brown, Analog Devices and NPC correspondingly. All of these are single-supply and have differential current output with respect to mid-rail virtual ground. Of the traditional R2R ladder audio DACs, the only one still around is PCM1704. A lot of people on this board like old 16-bit chips like TDA1541 connected without digital interpolation filters (non-oversampled).
Digital interface receiver chips (like DIR1703) typically have clock-recovery PLLs built-in, but offer essentially no jitter attenuation in audio frequency band. Additional VCXO-based low-frequency PLL can be used to improve jitter rejection in audio band, but this is more complicated and is rarely seen in amateur designs. Possibly interesting one-chip solution for clock clean-up is CY23FS04 from Cypress Semiconductors, which is a digitally-controlled XO and clock buffer.
As for coupling DAC current output to tube output stages, I think the best way to go is a low-impedance step-up transformer. This gives you low-impedance load for DAC output, high signal input for tube stage, and passive third order RC-L-RC filter all in one
.
Personally, I have designed and build DACs around
PCM1730 and
NPC5865. (I also used a bunch of commercial DACs, including tubed one from Audio Note...)
