INTERACT FORUM

Please login or register.

Login with username, password and session length
Advanced search  
Pages: [1]   Go Down

Author Topic: Stereo Channels Reversed on DSD playback via DoP  (Read 5311 times)

Boom Boom

  • Recent member
  • *
  • Posts: 6
Stereo Channels Reversed on DSD playback via DoP
« on: March 12, 2016, 03:04:29 am »

Hello

I purchased 2xHD's "Audiophile Hi-Res System Test - Great Sampling Tracks Included" recording in 2xDSD format from HD Tracks.

I was playing my new download and noticed that the left and right channels are reversed. I was wondering if other JRiver MC users are experiencing this as well or if the problem is with my DAC. I am using a PS Audio Nuwave DSD DAC with JRiver MC21 for Windows 10 (version just updated).

To troubleshoot I visited the HD Tracks website and played the samples of the recording using the arrow icons and the proper channels played. This bypassed JRiver MC21. Next I downloaded some wave test files for left, right, both channels played. When I set the DSP Encoding to "none" the files played on the correct channels. When I set the DSP Encoding for either 2xDSD or DSD in DoP format, the channels were reversed. It did not matter whether the DSP Encoding was set to "None" or 2xDSD in DoP format or DSD in DoP format when playing the 2xHD test tracks. The right and left channels played on the opposite channel. This was the same for the test tracks where the recordings played bells off center to the left and to the right.

If this is a problem with the JRiver DoP output, can we expect a fix?

Thanks for your time.
Logged

RD James

  • Citizen of the Universe
  • *****
  • Posts: 1871
Re: Stereo Channels Reversed on DSD playback via DoP
« Reply #1 on: March 12, 2016, 03:32:45 am »

DoP plays correctly for me.
There are three possibilities:

1. The album you're testing has the channels reversed.
2. One of the connections from your DAC is flipped around.
3. Your DAC flips the channel assignments with a DoP signal.


It should be easy to test.
Add a Parametric EQ filter to mute the left channel.

When playing PCM, does the sound play from the left or right speaker?
When encoding to DoP, does the sound play from the same speaker, or the opposite speaker?
 
If both are playing from the right speaker, everything is set up correctly and that specific album has the channels flipped around.
If both play from the left speaker, you have something hooked up the wrong way round.
If PCM plays from the right speaker and DoP plays from the left speaker, something is very wrong with that hardware.

I think the last result is very unlikely, but if it is the case you probably want to either encode everything to DoP, or convert DSD to PCM on the fly instead of bitstreaming it.
Logged

Boom Boom

  • Recent member
  • *
  • Posts: 6
Re: Stereo Channels Reversed on DSD playback via DoP
« Reply #2 on: March 12, 2016, 05:29:42 am »

Thanks so much for your help RD

I tried that test and got unusual results. I found out that the PEQ in the DSP studio works for PCM files so long as I don't convert on the fly to DSD. If output encoding is set to "none" The channels play properly, they will mute and swap properly. I have JRMC21 setup to convert PCM on the fly. The same problems as playing DSD files come up.

My understanding is that to enable DoP you have to set the audio to allow Bitstreaming (DSD). When I play DSD files, left and right channels are interchanged. PEQ does not work, so muting either channel doesn't work, both channels still play but transposed. The swap channels feature (selected under mix settings) also does not work.  >:(

I have near identical setup in a different room. Only difference is PC processor CoreI5 vs. CoreI3. I get the same results. I still have MC20 loaded. I tried same tests using MC20 and got the same results as well. I will contact the DAC manufacturer.
Logged

RD James

  • Citizen of the Universe
  • *****
  • Posts: 1871
Re: Stereo Channels Reversed on DSD playback via DoP
« Reply #3 on: March 12, 2016, 05:47:08 am »

Bitstreaming bypasses all DSP, you should disable it for this test.
Instead, enable DoP encoding in the Output Format section of DSP Studio. You don't even have to be playing a DSD file.
Logged

Boom Boom

  • Recent member
  • *
  • Posts: 6
Re: Stereo Channels Reversed on DSD playback via DoP
« Reply #4 on: March 12, 2016, 02:07:49 pm »

RD your're a lifesaver!  :D

Long story short, I used the Parametric Equalizer 2 in the DSP Studio window to swap left channel for right channel and it corrected DSD playback.

I set Bitstreaming to "None" and enabled the Output Encoding to 2xDSD in DoP Format.  I reperfomed the test you suggested and the PEQ is now working for DSD playback. What I learned was without the output encoding all playback was PCM. The DSD files were converted to 176,400 Hz PCM. However the channels played properly. I reset the output encoding to 2xDSD in DoP format and the mute left channel test showed that playback through this encoder setting had left and right channels reversed. I used the PEQ window to add a mix filter using the add option and selected source "Left" and destination "Right." I selected for the mode "Swap (swap source and destination). I saved the settings and now it works properly.

Your recommendations encouraged me to explore the DSP studio functions and how to do it properly. I did a little more experimenting and found if I added a second filter to swap right source for left destination, the problem returned. I also found if I used one filter but swapped right source for left destination, it also corrected the problem. I started exploring the Volume leveler options. I noticed that it uses 176,400 PCM to analyze DSD playback. I'm on the fence as to whether to use it. I'll experiment some more by playing classical tracks to see if it actually preserves intentional volume differences between tracks in an album.

Once again, Huge Thanks!!!  ;D
Logged

Boom Boom

  • Recent member
  • *
  • Posts: 6
Re: Stereo Channels Reversed on DSD playback via DoP
« Reply #5 on: June 10, 2017, 04:07:24 pm »

Long term follow-up on this, RD warned that there could be a problem with the DAC flipping channels. I learned from the manufacturer that this was a known defect.  :-[ DACs were registered with PS Audio so still under warranty. I sent back under RMA# and recently returned with firmware update. No more need for the parametric eq filter to swap channels on DSD playback.

The parametric eq filter to swap channels worked for a while until I purchased DSD downloads with soft passages which were skipped over during playback. I did some tests and the skipping was due to the parametric eq filter.  ::)

With the firmware correction to the USB device on the NuWave DSD, Using bitstream setting on DSD allows DSD playback without DSP processing and corrects the skipping on these DSD downloads.

So if there are any NuWave DSD DAC owners with the channel swap problem, likely in your best interest to contact PS Audio to have corrected.  :D
Logged
Pages: [1]   Go Up