Thank you.

Now, my question is : How to find one with an AKM chip please ? Or is it impossible because RME has stopped AKM chip ADI-2 FS ?

Keep it like it is and be happy you don’t have to deal with all the DSD hustle.

Set Foobar to convert DSD to PCM and take full advantage of ADI-2’s capabilities, that soundwise by far outclass any theoretical DSD advantage.

Once you begin to use ADI-2‘s DSP functions you for sure will not want to miss them in favor of DSD direct.
Start with the “Loudness“ function.

Not speaking of theoretical advantages of the ADI-2's PCM capabilities, but in general this is really bad advice.
Converting DSD to PCM will loose you sound quality, very noticeably. Also, the conversion in Foobar is not the best out there.

Hehe, nice find. True, convenience is important. It's just that I was (and still am from time to time) on a research mission to discover what the best digital can do. And I hear big differences to when the signal is converted to PCM. Btw., I find it a bit bad that during recording with the Pro that I only can hear a "coarse PCM conversion" (very coarse, it sounds like it is using simple averaging of the DSD stream for every PCM tick) when listening to the RME "preamp" signal. I know it is done for it to show peak levels and analyzer, but I'd prefer to have an option to listen to the DSD or watching the numbers. It's not possible to switch, is it?

I can't comment on the DSD capability of the ESS chip, but it has some I guess.

Well, headphones are the wrong device to make such conclusions. In part analog and DSD are superior to PCM because of better phase information from which the brain derives the sound stage etc, which does not work with headphones.

But even then, I have a switch on my preamp where I can toggle vinyl and RME DSD recording of it, the vinyl is cleaner every time, still unclear why this is. Cables may be different too, which unfortunately can also play a huge role I learned (by listening). But can be the switched power supply etc, I will keep investigating.

Btw., one great thing about DSD is that if needed, you can convert it to an arbitrary PCM resolution, I'm not surprised that 96 kHz and 44.1 kHz are kind of incompatible.

I listen to my vinyl recordings via bluetooth in the car, and they sound great, better than CD actually (maybe cause of 24 bit, maybe cause my recordings lack some highs and the car stereo has too much highs). KaiserTone is the app I'm using on the iPhone, I believe it has a better DSD to PCM conversion than all apps I used (Foobar and the Tascam one actually) on my Windows PC.

Edit:
"Switched 192 kHz PCM<->DSD on ADI-2/4 Pro SE in the Analog Input menu, while monitoring through the headphone out on a Hifiman "

What do you even mean by this? Didn't I just tell you I cannot hear DSD while recording? It's deactivated. (I don't have the SE, but I think this should be the same for yours too). I need to wait until the recording is finished to play the DSD. Do you mean A/D conversion? This is not what you hear on your headphones, you always hear PCM while in preamp-mode.

And if you use the headphone amp of the ADI-2, DSD is deactivated too, because it doesn't have analogue volume control.

Please also check my edited, enhanced response. I'm not saying my test is perfect, I need to get same cables if possible to do such a test, but there is always some harshness (not as bad as PCM harshness ;-)) on the RME chain, which I don't have on the pure vinyl playback.

How do you monitor analogue? Analogue gear? Speakers without DSP?

What I'm saying, -correct me somebody if I'm wrong- I think this would be the same for the SE:

The ADI-2 has 2 sound chips (AKM), and as far as I understood if you record, one chip is used for that task, converting analogue to digital. That is what the setting you are using is affecting.

If you want to monitor it, the recording stream is copied to the second chip, but since the unit also displays loudness and spectrum it ALWAYS converts this stream to PCM.

If you want to check DSD, you first need to record (I use VinylStudio), and if you then play back the DSD file, the unit has one free chip for this task.

And that was what I was criticizing earlier. I mean, I like that you can monitor what the A/D is doing, and adjust the analogue chain accordingly, especially tuning loudness, but still it's not a true representation of the signal if you record DSD. The general sound signature - bass vs. highs - is right, but playing back the DSD file afterwards is WAY smoother.

Thanks for correction, indeed I thought the DAC chip could do ADC as well, but it's another chip.
I just looked into the manual, and found that the second DAC chip is basically only used for headphones 3/4, so I never use it.

Overall, this is now still a bit unclear to me, I mean I've been hearing this clearly. But I always used the preamp mode to monitor. I never used the AD/DA mode. Is it better?

Because in the manual I found:
"... 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 Pro."

Also Preamp mode:
"... The below diagram shows that the analog input is sent to all digital outputs simultaneously. Any
DSP setting (EQ, phase etc.) of the analog input will affect all outputs. ..."

For the AD/DA-mode, no such statement is given?!

So you are saying: "DSD is converted and downsampled for the meter- and analyzer-display only, this works independent from the audio monitor."

Generally, it makes sense to me, that the DSP is not used for DSD monitoring, but does that hold true for the preamp mode? Also while studying the manual, I found that both the DSP as well as the DAC is capable of converting DSD to PCM, which makes sense in regards to the DSD Analyzer, but is a source of confusion. On the other hand, probably the DAC conversion is of higher quality, such that I didn't hear the same level of difference when toggling "DSD direct", as I hear while monitoring DSD via the preamp mode!

"And here’s the “sound difference” between DSD-PCM and DSD direct (ADI-2 Pro only):
DSD direct is 1dB quieter than DSD-PCM!"
Yes, I see that, it's always at -1 dB for me during DSD recording/playback.

Too bad, the ESS DACs don't offer "DSD direct", but I cannot tell how they sound, I never listened to them. Different chip manufactures have different strategies and that's fine. I know 1-bit DSD is not the only way for high-resolution PDM audio, I think that's what ESS is doing? Multi-bit PDM.

Something is off then, maybe a bug?

I've been using the ADI now for over a year, so I'm pretty sure I can trust my ears on that. But in case I wanna do a blind test, the only option I have available is to record ADIs output into a "cheap" interface, no DSD, max 192 kHz I think.

I haven't really recorded much PCM, just a few tests. DSD always sounded better, clearly better than 768 kHz PCM. So I don't know how the monitoring sounds when recording PCM, maybe it's not even related to DSD?