Topic: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

I read through the manual, but in the end, am still not sure, whether I understand DSD playback in the ADI-2/4 Pro SE properly.

IF DSD would be processed inside the unit as "DSD-ish" as possible, then the DSD-chip would convert it to an analog signal straight away, with no more "digital interference". Hence, the unit would put out an analog signal with a fixed level.

But as far as I understood it, the level/volume of the output signal can be adjusted in the ADI-2/4 Pro SE. Since this is not done by an analog potentiometer, I assume, that this must be done digitally.

Does that mean, that DSD will be converted to PCM, then fed into a digital processor, that will process volume level in the PCM domain, and only after these stages, the signal will be converted to an analog signal?

In other words: If that is the case, then DSD playback in the ADI-2/4 Pro SE is not "pure DSD to analog", but involves "downsampling"/converting to PCM: So the major arguments for DSD are obsolete?

Please correct me, if I'm wrong and please explain, how volume control is done in the ADI-2/4 Pro SE (if done inside the PCM domain: at what samplerate/bitdepth - if done differently, please specify). And/or is there a way to leave the line level output on the back of the ADI-2/4 Pro SE fixed (aka "untouched DSD") and only process volume for the headphone output?

Thanks for helping me understand that issue.

2 (edited by KaiS 2025-09-04 05:56:15)

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

DSD will be fed to the DAC chip as real DSD, NOT converted to PCM.
The DAC chip has a volume control for DSD signals built in.

At this point ESS does not disclose how exactly that’s done, see:
https://forum.rme-audio.de/viewtopic.ph … 06#p183706

Both channels of ADI-2/4 Pro SE are handled identical in this regard.


Only for the meter/analyzer a conversion to PCM is done.

See manual chapter 8.8:

DSD can not be processed digitally. Therefore DSP functions like Bass, Treble, Loudness, EQ etc. are disabled in DSD mode. The volume control is no longer done by the DSP, but the DAC chip. You won’t notice that, volume operation at the ADI-2/4 Pro SE is seamless and behaves identical in any mode.

In DSD mode the DSP performs an additional DSD to PCM conversion, to be able to show the audio signal on the level meters and for the Analyzer – another unique feature of the ADI-2 series.

3 (edited by dvdr 2025-09-04 08:33:33)

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

KaiS wrote:

DSD will be fed to the DAC chip as real DSD, NOT converted to PCM.
The DAC chip has a volume control for DSD signals built in
….
In DSD mode the DSP performs an additional DSD to PCM conversion, to be able to show the audio signal on the level meters and for the Analyzer – another unique feature of the ADI-2 series.

Thanks Kai for taking your time to explain this. I knew about the PCM conversion for metering, as stated in the manual. But never had a clue about how volume control was done. With my limited knowledge, I could only imagine PCM conversion for volume control in the outputs as well. But now I know, that it’s done inside the ESS chip - in what ever magical way.
I am sure, that the RMe engineers were perfectly up to the task to properly implement it.
Thanks for the link: it was an interesting read, including some additional links there!

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

Hi dvdr. After reading your posts, I believe you are interested in playing DSD with no further processing until the DA stage. It seems that wiht ESS based DACS this is not guaranteed and you should go to an AKM based DAC option. The ADI-2 Pro FS R Black Edition is AKM based and you can configure it in DSD Direct mode (no further processing, no volume control, no DSP, no nothing...) and in non DSD Direct Mode with the same behavior as the ESS based (PCM conversion to volume control).

5 (edited by KaiS 2025-09-05 11:48:13)

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

acatala wrote:

…  playing DSD with no further processing until the DA stage. It seems that wiht ESS based DACS this is not guaranteed and you should go to an AKM based DAC option. The ADI-2 Pro FS R Black Edition is AKM based and you can configure it in DSD Direct mode (no further processing, no volume control, no DSP, no nothing...) and in non DSD Direct Mode with the same behavior as the ESS based (PCM conversion to volume control).

This is not quite true.
The ESS DA-chips do handle DSD natively, do NOT convert to PCM.

They have the big advantage over AKM-DA chips that they offer a chip-internal volume control, that is seamlessly integrated into ADI-2.
I’d consider the ESS the more advanced solution.

It‘s not disclosed how exactly the ESS chips does handle volume control, but measurements hint to, that DSD‘s advantages of very high audio bandwidth and others are maintained, see here:

https://archimago.blogspot.com/2022/06/ … i-dsd.html
The ESS chip behaves like any other “DSD-direct”-chip when feed with DSD.

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

KaiS wrote:

The ESS DA-chips do handle DSD natively, do NOT convert to PCM.

Hi KaiS. I am not so sure about that point. When I purchased my ADI-2 DAC FS, I went after a second hand v2 model with AKM chip over a new v3 with ESS chip because of this.

For DSD related information, I take into account the information from Jussi Laako from Signalyst. He has lots of posts regarding recommended DSD DAC on other sites, for example Roon User Forum. I find Mr. Laako a reference on DSD.

Worth it DSD vs PCM? I can't answer that.

7 (edited by KaiS 2025-09-05 14:13:45)

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

Look at the link to the measurements:
The whole ESS behavior is DSD-direct-like, e.g.:

• The jitter does not cause sidebands like unavoidable with PCM, but ends up in the broadband noise-floor, like is typical for DSD.

• Ultrasonic bandwidth isn’t PCM-like brick-wall limited, just rolls off like low-order analog filtered.


Practically, having a volume control when using DSD (without PCM conversion) is very handy and increases the usability of ADI-2 for most.

The other way round: ADI-2’s DSD-direct (on AKM) is useless if you want a headphone amp, as 'phones out is purposely switch off in this mode on AKM-equipped ADI-2’s (to protect 'phones and user’s ears).

You have to switch off DSD-direct then, which means all ADI-2 CAN play it on 'phones, but without the DSD-inherited advantages on the AKM-versions.


IMO ESS is the better choice, no matter what’s going on in the chip.

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

KaiS wrote:

IMO ESS is the better choice, no matter what’s going on in the chip.

However in my opinion, the best choice is the one that fulfills the requirements.

If the requirement is to use the ADI-2 device as a headphone amplifier you should discard the DSD Direct mode, so you should go for a ESS based ADI-2 or for a AKM based ADI-2 disabling the Direct DSD mode.

But if you think/need that DSD is the way to go, for whatever reason you have, and you have taken your time to implement an outsourced system in order to convert on the fly PCM into DSD, for example using Signalyst's HQPlayer, then for coherence you would want to keep untouched the task made by HQPlayer until de DA stage and, in the case of RME's DAC, this is accomplished only by the AKM chips in DSD Direct mode. This way uses de ADI-2 as simple DAC, that's the price to pay.

Not every DAC built upon an AKM chip seems to rightly implements the DSD Direct feature as RME ADI-2 does. Even for the luxury act of using an ADI-2 as a "simple" DAC and getting rid of most part of its features, worth it buy one of this wonderful devices.

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

I don’t get the point in converting PCM to DSD by a player soft.

Why convert into a very feature limited audio format if the advantages of the format are already lost in the source?

Do you think the (lossy) conversion will bring back that advantages (rhetorical question)  – the answer is no, of course not, what’s lost is gone forever.


Inside the DAC chip such a handling is done anyway (*1), but with two advantages using PCM up to there:
• You still can use all the sound-improving features of ADI-2.
• You can use ADI-2’s volume control even on AKM-equipped models.


(*1)
That’s exactly what DSD is about, storing the working-format that oversampling AD- and DA-chips are using just next to their analog stage anyway, bypassing the noise shaping and other DAC-chip internal processings.

This makes sense only in a pure DSD signal path without any PCM inter-steps.
Native DSD recordings only very few exist, as it’s impossible to work with the DSD format in the typical way music is produced.

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

In other words, DSD is essentially a marketing product.
For the consumer, it means higher costs and significantly greater storage requirements.
All disadvantages lie on the consumer’s side, while real benefits are absent.
The format introduces unnecessary complexity at a higher price without delivering value.

BR Ramses - HDSPe MADI FX, M-1620 Pro D, 12Mic, UFX III, ADI-2 Pro FS R BE, Nuendo 15, Win10 IoT Ent

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

There are a few analog tape to DSD recordings.
E.g. MFSL, after some discussions, disclaimed their latest analog tape to analog vinyl re-issues incorporate a DSD inter-step.

I didn’t check if these transfers are published, maybe or maybe not, MFSL might not have the license to do so.


Personally I prefer either the original releases or very good remixes like the ones from Steven Wilson.

They are based on the original multitrack tapes, giving him the freedom to let everything shine in a new, clearer light while he’s still working faithfully to the original production.

Good example:
Jethro Tull, Songs From The Wood (The Steven Wilson Remix):
https://tidal.com/album/76176162

The original 1977 album (vinyl) sounds a bit muffled, which made me not picking it too often.
The remix is pure fun to listen, if you like the music.

Things like that make a real “night and day difference”, not mostly theoretical advantages of format switches.

Find good music, listen and enjoy!

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

Hi KaiS and ramses.

I use PCM most of the time. My ears can't distinguish between digital formats nor sample rates. I am just describing you the scenario of Hi-Fi DSD users.

DSD conversion on-the-fly is not about recovering lost information. If you have instersest in expanding your knowledge on this field , I would recommend you contact Jussi Laako from Signalyst. He is a DSD master, I mean it.

Signalyst software is a wonderful piece of software, not just for DSD conversion. It's not expensive, but the hardware you need for running can be. I appreciate Signalyst's software but, as I said before, I can live with non-upsampled PCM audio... and that's is what I listen to.

Let's enjoy music all together!! :-)

13 (edited by KaiS 2025-09-08 07:55:11)

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

In my studio I can clearly distinguish between native recording with sample rates of 44.1 kHz versus everything higher.

44.1 kHz can be improved by choosing a DA-filter that has a better compromise between frequency- and impulse-response and aliasing suppression.

The standard “Sharp” filter is frequency linear up to 20 KHz audio bandwidth, almost completely avoids aliasing, but has a tendency to smear the treble.

I prefer “Slow” with the AKM equipped ADI-2 Pro, and SD LD and Brickwall with the ESS ADI-2/4 Pro SE.

In exchange for a tiny treble rolloff and a little more aliasing (except Brickwall) in the top octave they give me better resolution of treble instrument’s transients, e.g. it’s easier to distinguish between hihats and shakers in a mix, and the overall sound is more transparent.

I clearly dislike the “NOS”-filter, it puts a layer of “fog” on the music that I attribute to aliasing noise which this filter doesn’t avoid at all.
It’s too far optimized towards impulse response for audio listening.

But, NOS is a good choice if one uses ADI-2 as measurement frontend to generate short impulses.


This all is relevant with sample rate of 44.1 kHz, lesser so with 48 kHz, but not at all with anything higher.

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

acatala wrote:

DSD conversion on-the-fly is not about recovering lost information. If you have instersest in expanding your knowledge on this field , I would recommend you contact Jussi Laako from Signalyst. He is a DSD master, I mean it.

There is a misunderstanding. I did not say conversion to DSD would have something to do with recovering lost information.

My statement is that upsampling or conversion to DSD can't make the audio any better compared to the audio quality of the original. You can only avoid some disadvantages of some D/A filter for single speed, as pointed out by KaiS above and several times in the forum. At double/quad speed you hear no difference between D/A filter anymore.

BR Ramses - HDSPe MADI FX, M-1620 Pro D, 12Mic, UFX III, ADI-2 Pro FS R BE, Nuendo 15, Win10 IoT Ent

15 (edited by acatala 2025-09-08 10:08:32)

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

ramses wrote:

My statement is that upsampling or conversion to DSD can't make the audio any better compared to the audio quality of the original.

I agree and that is why I don't upsample nor use DSD conversion on my Hi-Fi system. I can't even distinguish between 44,1/48 kHz sample rates and higher as KaiS does. So, for me (and my ears) there is no point in upsampling.

Ironically, I discovered and bought an ADI-2 DAC (AKM based) just because I wanted to experiment with DSD direct. I have ended using the ADI-2 DAC without upsampling nor converting to DSD. IMO, there is no need.

16 (edited by KaiS 2025-09-08 12:43:15)

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

acatala wrote:

I can't even distinguish between 44,1/48 kHz sample rates and higher as KaiS does.

It‘s easier if you come from an analog source and switch a whole chain of AD to DA conversion.

Like in a studio recording, or with ADI-2/4 Pro SE and a vinyl turntable connected.

For vinyl listening with ADI-2/4 Pro SE I run it on 192 kHz.
A bit of overkill, 96 kHz is equally good, but the higher sample rate doesn’t cost extra in this case smile

17 (edited by Ivodam 2026-04-13 14:24:06)

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

dvdr wrote:

I read through the manual, but in the end, am still not sure, whether I understand DSD playback in the ADI-2/4 Pro SE properly.

IF DSD would be processed inside the unit as "DSD-ish" as possible, then the DSD-chip would convert it to an analog signal straight away, with no more "digital interference". Hence, the unit would put out an analog signal with a fixed level.

But as far as I understood it, the level/volume of the output signal can be adjusted in the ADI-2/4 Pro SE. Since this is not done by an analog potentiometer, I assume, that this must be done digitally.

Does that mean, that DSD will be converted to PCM, then fed into a digital processor, that will process volume level in the PCM domain, and only after these stages, the signal will be converted to an analog signal?

In other words: If that is the case, then DSD playback in the ADI-2/4 Pro SE is not "pure DSD to analog", but involves "downsampling"/converting to PCM: So the major arguments for DSD are obsolete?

Please correct me, if I'm wrong and please explain, how volume control is done in the ADI-2/4 Pro SE (if done inside the PCM domain: at what samplerate/bitdepth - if done differently, please specify). And/or is there a way to leave the line level output on the back of the ADI-2/4 Pro SE fixed (aka "untouched DSD") and only process volume for the headphone output?

Thanks for helping me understand that issue.

Hi DVDR,

I came across your topic, which is already some months old, decided to write my opinion, because you might be still interested in the DSD conversion theme, a theme, which is full of incorrect, sometimes misleading information.
Above all, it is good to understand that there is not such thing as DSD-chip. The nature of this format DSD is such, that it can be converted to analog form with the help of discrete designs, using resistors, capacitors or transformers. The mass available dac chips on the market always manipulate the DSD signal in order to convert it (they manipulate as well the PCM signal) with the so called modulators.
There are DSD-Only-Dacs available, without chips, but they are usually rather expensive.
But you are right that it makes only sense to have the DSD file converted in its original 1-bit form, no question about it.
Every digital-to-digital conversion brings loss of quality, whatever you might here or read...

18 (edited by Ivodam 2026-04-12 07:30:34)

Re: Pls. help understand DSD / volume control in ADI-2/4 Pro SE

KaiS wrote:
acatala wrote:

…  playing DSD with no further processing until the DA stage. It seems that wiht ESS based DACS this is not guaranteed and you should go to an AKM based DAC option. The ADI-2 Pro FS R Black Edition is AKM based and you can configure it in DSD Direct mode (no further processing, no volume control, no DSP, no nothing...) and in non DSD Direct Mode with the same behavior as the ESS based (PCM conversion to volume control).

The ESS DA-chips do handle DSD natively, do NOT convert to PCM.

This is not 100% true. The Sabre chips take the 1-bit DSD stream and convert (requantize it) it into a multi-bit format (typically 6-bit), while keeping the high sampling rate. This allows some digital processing, such as volume control. This is not PCM, but no more pure DSD either. In some literature I have seen they call this format DSD-wide. I do not believe this goes without quality loss.