Another point worth mentioning is that
cat /proc/asound/card*/pcm*p/sub*/hw_params
gives me the following output each time I play the DSD256/512 songs.
access: MMAP_INTERLEAVED
format: S32_LE
subformat: STD
channels: 2
rate: 384000 (384000/1)
period_size: 16384
buffer_size: 65536
Looks like thereās a volumio audio server running there and it ends up being converted to 384k PCM there? First DSD256 to 1411.2/24 PCM by MPD and then to 384 by volumio server? And DSD512 to 2822.4/24 PCM and from there to 384k PCM?
Would you see the DSD256 noise hump if it converts to PCM384kHz?
There is no noise hump or digital images visible with PCM353k and 384k
Depends on how the conversion is done yes, up to 192 kHz. Plus any image parts of the hump that come through if thereās no further digital filter or a weak one. If it is āNOSā at 384k, then any hump that ends at 192k would continue from there on as an image.
Remember that the first image band is inverse frequency.
Given the potential unknowns with DSD input, it is best to feed this particular DAC PCM353kHz as I mentioned some weeks ago. The result is very good,
If you want true DSD to analogue conversion, best to remove all doubt and simply get one of the other recommended DACs.
I still have the DAC but not spending more time investigating DSD with it because there are other options,
So I have the user manual and it does not mention anything about activating a DSD Direct mode. Even though the DAC chip obviously has this feature.
Bummer. (10 chars)
Iāve asked the manufacturer and will report back. It wouldnāt be the first time I got a manufacturer updated their user manual (if they have actually made it possible to activate the chipās DSD Direct mode)
I think you are also tired of mentioning that you measured the DAC very well with PCM353k and thus recommend this setting. I trust you completely here and am also very grateful for the recommendation and also other DAC recommendations (the S.M.S.L. D6 is on order).
I would just like to continue your research and verify the true native DSD reproduction of the DAC, even if you are convinced that this will come to nothing.
But I am mainly interested in upsampling with the HQPlayer with native DSD playback as high as possible. I would like to know what it takes to do this. Because this DAC will not be the only one that supports DSD natively according to the chip used, but fails because of Linux compatibility.
The questions I would still have now would be, via which channel did you contact InnoMaker? I have sent an email to support@inno-maker.com, but unfortunately have not received an answer yet. And did you ask Ian Canada about his ESS controller or MonitorPi, whether you can get native DSD support through it?
Yes thatās the correct email. What was the exact question you asked them? Can you copy and paste it? I recall above there was some confusion about DoP so if the question to them wasnāt clear, that makes it harder for them
We had a long chat about his fully featured stack. He fully understood my aim of ānativeā DSD256 playback but from our chat, it was highly likely not possible. I tried to connect all the dots and everything was trending to the same result as with the Innomaker board. I wasnāt keen on spending so much $$ for potentially the same result.
If it was possible the ESS controller or MonitorPi would work, I would imagine he would have brought those up as a solution.
Thanks, but my hopes are not that high.
As to my knowledge, so far there is no 4499EX out there with direct DSD mode.
Iām interessed if your DAC HAT supports native DSD playback with the HQPlayer.
My main goal is to use your DAC HAT as a NAA Endpoint for using the upsampling function of the HQPlayer.
Unfortunately NAA detects only up to 384-KHz/32-Bit(PCM) as the āAllo Katanaā only supports only up to 384-KHz/32-Bit(PCM).
Is there anything you need to enable to support DSD natively? Or is there any other device tree overlay that supports DSD natively?
Do you know what Volumio is doing in detail to support the native DSD playback? Is there something that proves that the output is really native DSD in Volumio and not DoP, as the Allo Katana only support DoP and not DSD natively? (like any logs)
This is the copied text from the email.
I asked Ian again in a thread because he has just released the second version of his Dual Mono DAC.
I have tested/measured that Gustard A26 with fixed firmware works correctly at DSD128 and DSD256. Since the AK4499EX chip is only capable of running at 128fs or 256fs conversion rate. They fixed the firmware after a bit of discussion.
SMSL claims to have DSD Direct support on their AK4499EX DACs, but it needs to be verified first.
There is nothing really technically wrong with DoP.
For example with the RME ADI-2 DAC, it only supports DoP - but the AKM models are still highly recommended
I think you are still confusing DoP with actual permanent conversion of DSD to PCM
And when you mention NAA and HQplayer they wonāt have a clue what this is - unless theyāve explored since my emails with them
I received feedback from innomaker today, which left me a little speechless. But I suppose these are the hard facts that we have to accept. I am posting here the answer to my questions mentioned above:
Refer to below screenshots, This DAC PRO hat is connected to the IIS(PCM) port of the Raspberry Pi. Not work on the DSD native connection mode.
The main chip es9038 can support DSD512 native data, but the Raspberry Pi canāt support DSD native connection mode.
In fact, all the raspberry pi audio hat is working on DSD (DoP) or D2P mode, not support the DSD native mode. No matter how you set DSD mode on Volumio.
Now the āAllo Katanaā only supports PCM-384Hz (limited by the IIS port of Raspberry Pi), so the DoP has be limited on DSD128 mode.
So if you want the native DSD higher on Raspberry Pi, the best way is to buy the usb audio which is support the DSD512 native really.
Would love to hear your thoughts on this.
No surprise at all, they are all well known facts
Confirmed - no option for the user to enable DSD Direct.
OK, no surprises there, so it is just as I expected.
DoP works thanks to the ESS DAC chip built-in DoP decoder. But of course that poses rate limitation due to marker overhead.
It would be possible to support native DSD though, but it would require suitable controller between RPi I2S and the DAC chip. Completely doable, but nobody has done it yet. That would allow max DSD256.
There are SoMs on the market that can do 8 channels of DSD512 natively. But the Broadcom chip used on RPiās doesnāt have such features.
The only controllers I know are the ones from Ian Canada:
DocumentDownload/ESScontroller/ESScontrollerManual.pdf at master Ā· iancanada/DocumentDownload (github.com)
Or MonitorPiPro with build in ESS Controller:
DocumentDownload/MonitorPi/MonitorPiPro/MonitorPiProManual.pdf at master Ā· iancanada/DocumentDownload (github.com)
and no intentions to change that?