I found a link talking about ess chip with the DSD file volume control:
https://www.computeraudiophile.com/forums/topic/19381-ess-sabre-and-dsd-volume-control/
Here is John Siau's explanation of how DSD volume control is done in the Benchmark DAC2. The DAC2 uses the ES9018 DAC chip.
MW: How do you handle volume control in that final output stage? Do you convert to analog and then turn it up and down.
JS: We actually don’t. We do process that at the high sample rate and we have multiple 1-bit converters that are available to us. So the increase in word length that we get as a function of that volume control makes use of the redundant 1-bit converters that we have running in parallel.
MW: I see.
JS: So we’re not converting it…in a way you could look at that as if it’s PCM because there’s multiple 1-bit converters summed together in the analog domain. But that’s what you have to do to get volume control to work. The good thing is we don’t take it from 1-bit to multi-bit and back to 1-bit before we convert it to analog.
MW: Yep, as you were saying before.
JS: Instead of sending identical DSD signals to sixteen balanced 1-bit converters that are wired in parallel, we start sending different DSD signals to reduce the signal amplitude. All summing occurs in the analog domain. It is very cool!
I was always under the impression that you had to play DSD at full volume and use the analog volume to adjust. You learn something new everyday.
I guess I’ll test for myself on the D50.
When did DACs offering volume control become a thing anyway? I always thought it was the Amp’s job to control volume.