What does a DSD capable DAC do?

In a recent Ask Paul, he mentions that a dsd file can be played directly into an amp and produce sound. What exactly does the DAC bring to the playback process with dsd?

Timing, stability on the power supply rails, upsampliing of PCM, a volume control, receiving and decoding of USB, I2S, etc…

Without a great clocking system, the jitter can mask many of the details and timing of the music.

Any power noise goes right into the amp and hence shows up as noise in the audio which also masks details, etc. Among other things this greatly curtails the ends of the decays of each note, etc.

As with much of life, the devil is in the details.


Thanks for your explanation. Does that stuff happen in real time, or is the incoming stream buffered before or after processing?
Sorry for the elementary questions.

In the case of the DS, essentially in real time. There’s a small buffer (upto several thousand samples) which allows the DAC to lower jitter by having a long time to react to changes in the input clock but that’s short enough that there’s no appreciable lag in the music. Some users prefer to do the conversion to DSD in a separate program on their PC offline or in real time with their player (most playing software can convert to DSD these days.)