The key here is the volume control technology. There are only three that compete with the very best preamps:
1) DACs that control volume by adjusting the reference voltage
2) Transformer-based line-stages added to DACs, such as this one:
http://app.audiogon.com/listings/solid-state-music-first-classic-silver-cryoed-transformer-line-stage-2013-06-29-preamplifiers-97759-black-butte-ranc-or
3) Line-out of a high-drive output DAC to amps directly and use digital volume control - least attractive and most dangerous.
All of these require that the output stage of the DAC be as good as the very best preamps on the market, including drive strength, output impedance and power delivery.
Steve N.
Empirical Audio
1) DACs that control volume by adjusting the reference voltage
2) Transformer-based line-stages added to DACs, such as this one:
http://app.audiogon.com/listings/solid-state-music-first-classic-silver-cryoed-transformer-line-stage-2013-06-29-preamplifiers-97759-black-butte-ranc-or
3) Line-out of a high-drive output DAC to amps directly and use digital volume control - least attractive and most dangerous.
All of these require that the output stage of the DAC be as good as the very best preamps on the market, including drive strength, output impedance and power delivery.
Steve N.
Empirical Audio