TEAC UD-501, r8Brain up-sampling, DoP 1.1, Integer Mode

When did this change?
I just noticed that my DAC (TEAC UD-501) does not recognize up-sampled (modulated) PCMxxx → DSD128 DoP 1.1 signals unless Studio has ‘Integer Mode’ enabled… If ‘Integer Mode’ is not enabled even with r8Brain engaged, the PCM signal is sent as the native sample-rate to my DAC… In my case, these files are 44.1kHz, 192kHz or 352.8kHz… Disabling ‘Exclusive Mode’ does not change the behavior.

*The r8Brain “Forced up-sampling type” is set to: “to DSD” and “DSD target rate” is set to: “DSD128”

Only when ‘Integer Mode’ is enabled will the up-sampled PCMxxx → DSD128 via DoP 1.1 signal be recognized in the DAC as a DoP signal playing DSD 5.6MHz.

  • Is this unique to the TEAC UD-501?
  • Is this new in Studio 2.2.3 or have I just missed this since the version 2.0 release?
  • Is this related to r8Brain in some way?
  • Is this expected behavior?

Any insights are appreciated…
:notes: :eye: :headphones: :eye: :notes:

Something has certainly changed in Studio’s handing of DSD files - I tried to draw the community’s attention to the handling of Inter Sample Overs in DSD files by Vers 2 onwards with no luck in another thread. No comment from Audirvana or any other folk having this issue.

Files with as little as +0.2dB TLP have massive breakup and distortion where version AS 1.0 through 2.0 played them without problem (as does legacy 3.5) - this seems to have happened at the tme AS was ‘optimised’ for Mac OS Ventura.

I don’t have problems with playback with up-sampled (modulated) PCMxxx → DSD128 or native DSD files, outside of what I just described in my post…

Are the DSD files you have problems with inter-sample overs, extracted from SACD ISO files?
Are you having Audirvana down-convert DSD to PCM?

:notes: :eye: :headphones: :eye: :notes:

I tried streaming with Origin at all DSD rates from DSD64 to DSD512 without an issue.

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Adding to my own post…
@Antoine … Can anything be done about the loud “Tick” when changing sample-rates from and to DSD? sometimes it is slightly muted and sometimes it isn’t and it is loud, especially switching from PCM to DSD … Adding latency to the sample-rate change does nothing and it seems worse in ‘Integer Mode’…
This is an ongoing annoyance to say the least…

:notes: :eye: :headphones: :eye: :notes:

They are .dsf files from PS3 rips of SACDs. The source may be the cause of the Inter Sample Overs but the source is not the problem with Audirvana as at least two files now which played fine before (and play fine with other versions of Audirvana and with other players). I neither up nor downsample with AS.

It appears that the inter-sample overs have always been there from the extraction of the .iso files… You may want to go back and use a better extraction application that will normalize those spikes… The audibility of these now, illustrates the accuracy of the Audirvana audio-engine in delivering the true nature of the digital-audio data… It is the DAC that does not handle the inter-sample overs well…
:notes: :eye: :headphones: :eye: :notes:

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I forgot if you where on a Windows PC or on a Mac. On my (Windows) system I get the loud ticks as you describe when I use ASIO. When I use WASAPI or Kernel Streaming the ticks are gone. I have a Topping D90 DAC directly connected via USB to my NUC. When I use Foobar or JRiver no ticks occur at all.Only Audirvana does that on my system. I have this issue with Audirvana since 3.5. I had it in Studio and I also have it in Origin. Luckily using WASAPI is a good workaround for me. But, as you said, this is an ongoing annoyance.
Of course the WASAPI mile(s) on your system may vary.

@AndyLubke …Thanks for the input…
macOS version 12.6.2 (21G320)
MacBook Pro (15-inch, 2016), 2.7 GHz Quad-Core Intel Core i7, 16 GB 2133 MHz LPDDR3
USB to DAC with a iFi Audio iGalvanic 3.0 inline on a USB 3.0 input feed delivering USB 2.0 output signal to an UpTone Audio USB 2.0 two-inch ‘cable/dongle’ adapter feeding signal to the DAC.

Answering my own question with this insight from an iFi Audio Blog post attached here…
I have generally understood the reason, but hoping for some resolution or consistent muting of the “pop” in the audio-engine… I’ve also thought it may be the UD-501 itself, in the manner it handles switching from PCM to DSD sample-rate changes over DoP…

This article brings more focus to the issue of the persistent sample-rate change “pop”:

“Pop” goes DSD? Why does this happen?

From the above blog post:

  1. The only way to reduce this ‘pop’ is to run a small period of silence during these changes. In other words, the playback software must handle this correctly and play a short silence before it stops sending DoP markers.

The question that comes to mind: “Is this transition in sample-rates from PCM to DSD or visa-versa, being implemented properly in Audirvana Studio?”

:notes: :eye: :headphones: :eye: :notes: