Channel Mapping Issue for Quad DSF Recordings

Hello, all. I have been working with Thierry Villard from Home Audio Fidelity on developing sound correction filters for my various stereo and multichannel systems at home. All has been going well, with the exception that Thierry cannot figure out how to configure the channel mapping for 4.0 multichannel albums, such as the Chicago Quadio versions. Everytime he redoes the filters, we only get the front two speakers playing out. No problem for 5.0 or 5.1 music – that plays fine. I have tried 5.1 and 7.1 with both swapping and not swapping rear channels. No luck.

I am attaching a couple of the test filters for Roon convolution that Thierry prepared, as he suggested I share with the Roon team in trying to figure out what’s going on here. Thoughts appreciated. Thanks. JCR

PS Oh, I can’t upload the zip files that represent the filters. Can someone explain how I can do that here?

Hello @Jeffrey_Robbins,

Thanks for contacting support regarding this issue. Can you please let me know more information regarding your setup here? We generally require the following information when submitting a report such as yours:

At the very minimum, please let me know the Operating System, Specs and version of Roon you’re using on your Core and which DAC you have and how it is connected to the Core. Any additional information that you can include from that guide would be much appreciated. As for sending us the .zip of the filters, I will PM you shortly on how to upload those to our servers for analysis.


Hello, @noris. Thanks for the quick response. First, I’ve uploaded five files for you to the site you PM’d me, to wit:
04. Just You ‘N’ Me.flac

The first file is the standard 5.0 /5.1 set of filters that work fine across anything stereo or multichannel, DSF to 22/44.1, other than 4.0 content.

The third file is the crosstalk correction set of filters which, again, works for 5.0/5.1 across all content, other than 4.0 content.

The second and fifth files are the test filters that Thierry created to attempt mapping out the 4.0 content, without success.

The fourth file is a sample cut from Chicago IX Quadro, in 4.0 multichannel format 24/48 resolution.

Roon core is on an i7 server built by Small Green Computer (a CAPSZuma design). It is running Windows Server 2016 in desktop experience mode, as modified by Audiophile Optimizer with Roon server (a blank black screen) as the default login screen. DAC is a stack of three Musical Fidelity V-90 DACs arrayed together as a single DAC via miniDSP’s UDIO-8 box.

To show you signal path, here first is the standard set of filters playing a 5.1 file:

In Roon setup, this is setup as DSD convert to PCM, NO MQA support, max rates 24/192, MQA core decoder enabled, channel layout 7.1 with no swapping of rear and surround channels and channel mapping only. My system is 5.2, so 7.1 without swapping rear channels seems off, but that is the way that Thierry set it up and it works fine.

Switching to the no mapping filter, with no changes in the setup, the signal path looks like this:

The signal path looks the same if I switch to swapping rear and surround channels. If I switch to 5.1 in setup, the signal path is the same except that the channel mapping 5.1 to 7.1 line disappears.

Switching to the quad test filter, and set up as 7.1 with no swapping of channels and channel mapping in place, it looks like this for the signal path:

It looks the same on the signal path when selecting the swapping of rear and surround channels. When switching to 5.1, it looks like this:

Switching now to the Chicago file that I’ve sent you, here’s how it looks in the signal path with the standard filters, as 7.1, 7.1 with swap and 5.1. Note that in the standard filter format, Roon doesn’t even see the file as a 4.0 file. Weird, as you see that with 7.1 swap and 5.1, each as set out below.

I won’t go through the two test filters, no mapping and quad44, but you get the idea and if you do need me to run those and show the three different path choices for each (7.1, 7.1 with swap and 5.1), then let me know.

Thanks for the help. JCR

Hello @Jeffrey_Robbins,

Thank you for posting the screenshot and sending us the filters. I have started a case for you with our QA team who will look into this behavior further. I will be sure to let you know once I hear back from QA regarding this issue and I appreciate your patience while this case reaches their queue.


But of course. Thank you. JCR

Hello @Jeffrey_Robbins,

Sorry about the delay in getting back to you, we have been iterating with the development team about the expected behavior here. We continue to investigate a possible solution for the issue you are encountering regarding the 4.0 channel content mapping, but some further testing is required to make sure that it works under all possible conditions. Your incredibly detailed feedback has been invaluable to our diagnostic effort, so we thank you for taking the time to explain your setup in such detail. We hope to have a solution ready for you soon, and I will be sure to keep you in the loop.


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I appreciate the update @john. No problem — I have lots of music to keep me occupied whilst the team gets this sorted out. Cheers. JCR