• Registered: 2022-02-13
  • Posts: 3

Topic: DSD Direct - with ESS chip

I recently read the RME ADI-2 DAC FS manual again and found something about the DSD Direct on the Units with ESS chip:

Units with ESS chip
These chips do not support DSD Direct. Instead word is that the included, extensive volume control was designed so that it can even process DSD data without PCM conversion. Unfortunately official information on this topic is either vague or non-existent.
(https://www.rme-audio.de/downloads/adi2dacr_e.pdf Page34)

So now I'm a little confused, is DAC with ESS chip able to play DSD directly without converting DSD to PCM? And can control volume with the "DSD Direct" mode is on& be able to use headphones?

2 Reply by MC

  • MC
  • MC
  • Administrator
  • Offline
  • From: Germany/Thailand
  • Registered: 2007-04-06
  • Posts: 24,837

Re: DSD Direct - with ESS chip

You have to ask ESS about this, and I bet they won't answer. The data sheet does not include details about DSD support, so my vague statement is fully intentional.

You can learn something about ESS DSD playback quality here at Archimago's blog:

https://archimago.blogspot.com/2021/10/ … e-dac.html

Regards
Matthias Carstens
RME

MC's Website

  • ning
  • DAW Mastermind
  • Offline
  • Registered: 2019-06-08
  • Posts: 579

Re: DSD Direct - with ESS chip

> So now I'm a little confused, is DAC with ESS chip able to play DSD directly without converting DSD to PCM?

Based on the text, the answer is "don't know"


> And can control volume with the "DSD Direct" mode is on& be able to use headphones?

based on the text, there's no "dsd direct mode" for ESS chips.

  • ning
  • DAW Mastermind
  • Offline
  • Registered: 2019-06-08
  • Posts: 579

Re: DSD Direct - with ESS chip

Wow, MC is one second faster ...

  • Registered: 2022-02-13
  • Posts: 3

Re: DSD Direct - with ESS chip

MC wrote:

You have to ask ESS about this, and I bet they won't answer. The data sheet does not include details about DSD support, so my vague statement is fully intentional.

You can learn something about ESS DSD playback quality here at Archimago's blog:

https://archimago.blogspot.com/2021/10/ … e-dac.html

Thank you very much for your reply! Now I understand it

  • Registered: 2022-02-13
  • Posts: 3

Re: DSD Direct - with ESS chip

ning wrote:

> So now I'm a little confused, is DAC with ESS chip able to play DSD directly without converting DSD to PCM?

Based on the text, the answer is "don't know"


> And can control volume with the "DSD Direct" mode is on& be able to use headphones?

based on the text, there's no "dsd direct mode" for ESS chips.

Thank you! I think it's because of ESS's obfuscation of details (no one knows except...)lol

  • Registered: 2018-06-12
  • Posts: 42

Re: DSD Direct - with ESS chip

This has been discussed for so many years and while we still don't have clear explanation from ESS directly, some very clever people have hypothesised (some have done measurements too) that 1bit SDM (DSD) is converted to 5 or 6 bit SDM for volume control in the ESS chip - but the original sample rate itself is un-touched.

So if you feed the ESS chip with 11MHz (DSD256), there is no resampling.

Jussi of Signalyst HQPlayer has been discussing this for many years on forums. Here is one thread from 2014 but there is more at this site. Just search the forum for ESS and DSD

https://audiophilestyle.com/forums/topi … e-control/

  • Registered: 2018-06-12
  • Posts: 42

Re: DSD Direct - with ESS chip

This video is worth watching.

Interview with ESS engineer:

https://www.youtube.com/watch?v=TuEIs2PA1nU

Some interesting slides from the video:

https://i.imgur.com/8yOU8df.jpg

https://i.imgur.com/GgRIwQ9.jpg

https://i.imgur.com/2iNm0xE.jpg

  • Registered: 2018-06-12
  • Posts: 42

Re: DSD Direct - with ESS chip

Interesting thing here from the link I posted above, by Benchmark lead engineer John Siau

So here he is saying that DSD is not re-modulated at all

https://i.imgur.com/nfnZHnQ.png

  • Registered: 2018-06-12
  • Posts: 42

Re: DSD Direct - with ESS chip

Later in that same thread, there is a comment by Michal of Mytek who says something different.

Then later in that same thread, there is a comment by Renaissance Labs (former ESS employees?) that says something different again.

Nobody knows LOL.

11 Reply by ning (edited by ning 2022-06-27 00:54:41)

  • ning
  • DAW Mastermind
  • Offline
  • Registered: 2019-06-08
  • Posts: 579

Re: DSD Direct - with ESS chip

MC wrote:

You have to ask ESS about this, and I bet they won't answer. The data sheet does not include details about DSD support, so my vague statement is fully intentional.

You can learn something about ESS DSD playback quality here at Archimago's blog:

https://archimago.blogspot.com/2021/10/ … e-dac.html

Archimago recently posted another Chinese manufacturer's ESS DAC's DSD playback result.
https://archimago.blogspot.com/2022/06/ … i-dsd.html

Seems the issue (higher noise at higher dsd rate) is a topping product flaw.
Their competitor implemented it correctly and the product does not have elevated noise when playing higher dsd rate.

So to clarify --- MC's link only showed DSD playback quality on a flawed ESS implementation.
Good ESS implementation should not have this issue.