5.0 channel re-mapping

I want to say that, with the new v1.7 version, there are still issues with mapping 5.0 channel recordings to a 5.1 or 7.1 channel output if a Procedural EQ and/or a Parametric EQ is introduced into the signal path.

Is there a solution under consideration?

Moved this to support for you…note that due to the recent update resources might be a little stretched so know that someone will chime when they can.

Hello @mitr,

I checked our bug tracking system and I see a ticket similar in nature to the issue you are describing. It would be helpful if you could provide clear reproduction steps, along with the “expected” behavior and “observed” behavior as far as the channel mapping is concerned, so that we can get these reports merged and in front of the dev team.

-John

I am using an exaSound e38 8-channel DAC connected by USB and using the exaSound ASIO driver. The output is set in Roon for 5.1 because I have only 5.1 speakers even though the DAC can support 7.1. If I set it for 7.1, the results are the same.

  1. With 5.1 source files (DSF or FLAC), the channels map correctly without fault.
  2. With 5.0 files (the most common MCH format of modern classical recordings), the channels re-map to the standard 5.1 output format correctly, if there are no filters/EQ in the signal path.
  3. If I introduce a procedural EQ (add bass management) and/or a parametric EQ, the mapping of FL, FR and C are correct, LFE gets SL, SL gets SR and SR is silent. The drop-down signal path show that there is re-mapping before and after the filter(s).

Actually, I think the problem is that the re-mapping is after the procedural EQ and should precede it.

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Hello @mitr,

We were able to reproduce the behavior you are reporting. I have re-written the ticket and submitted it for developer feedback on the expected behavior here.

-John

Great. Looking forward to a resolution.

BTW, what I was attempting was to implement bass management for which all the tools necessary are available in Roon. It would be great if you could implement a DSP option for bass management so every user will not have to re-invent the wheel.

Hello @mitr,

Thanks again for the clear reproduction steps, I was able to get this in front of the development team for comment. They confirmed that Roon is behaving as designed in the outlined scenario, and asked that I open a feature request ticket for the functionality you are requesting.

Digging deeper, Roon’s Parametric EQ Mix feature needs to work in a multitude of different setups and does not have visibility into previous or proceding DSP operations. Having the Mix behavior change based on previous DSP operations opens up a can of worms that could break the Mix channel mapping in other ways.

As mentioned, a feature request ticket has been opened containing an outline for the behavior you’re requesting. In the interim, you may be able to reduce the friction encountered when playing 5.0 content by using Roon’s DSP Presets feature. You could dave a DSP Preset with the desired mix settings for 5.0 content and another preset for multichannel content with a LFE channel. You will be able to switch between presets on the fly on all platforms, including the Roon Remote app on iOS and Android.

-John

When I look at the signal path, there is a clearly implied orderly sequence of steps, a pipeline. Is this not so? and, if so, changing the order of those steps is all that is is necessary. If that is not so, what does it mean? Also, the exact operations of channel mapping steps that Roon inserts are not revealed.

Thanks. I look forward to a satisfactory resolution.

Not a useful suggestion, imho. This means that I would have to anticipate what channel maps are used by each recording I want to play and then, during playback, invoke a switch. C’mon. The most common discrete multichannel format for classical music is 5.0. Getting it to play properly should be a given or, at least, a high priority.

OK. Is there any progress with this issue over the past 4 months? Playback of 5.0 recordings is still impossible. (FWIW, 4.0 is fine.)

FWIW, here is the reason for me to bring this up again:

Hello Kal

I searched the roonKB and found this:

…Most musical content produced recently is either in either 2.0, 5.0 or 5.1. There is a small amount of 7.1, too, and a small amount of Quadrophonic content. Compared to these four formats, practically everything else qualifies as exotic in an audio/music context.

Channel mapping for 2.0, 5.0, 5.1, and 7.1 is straightforward, since each larger layout simply adds channels to the previous one. In these cases, Roon matches up the channels from the source material with the channels on the output device and fills any unused channels with silence…

Unfortunately, that is not so. I have raised the issue with them and they were able to reproduce the anomaly as I have described it: 5.0 channel re-mapping It is not an issue if one does not do any procedural filters in Roon. However, in order to use the DAC8 Pro in multichannel, one must (as you have indicated) configure it as a 7.1 (8channel) DAC. T

The consequence of this is that, to play it in a 5.1 system, one must set a procedural filter to divert Surround L/R signals to the Back L/R outputs. The result is that one gets incorrect mapping with or without the diversion of the Surround L/R. Either you get only the front L/C/R channels or you get front L/C/R + LS in the sub + RS in the LS speaker and nothing from the RS speaker.

Do you experience the 5.0 issue on both Windows and Linux? If so this is probably a channel mapping issue in Roon.

Yes.

@ support - I think I have either found a new anomaly / combination or I’ve set something up wrong!

Finally got around to ripping my 4.1 Pink Floyd DSOTM 96/24 DVD-A into FLAC today, which seems to show-up as 5.0 in the metadata.

Playing it through my Meridian 861v8 (7.1 channel) Roon always down-mixes to 2.0 regardless of the ‘Channel Mapping Only’ setting, which I’d hope would force multi-channel output, rather than stereo.

And, of course, the whole point of owning & playing the Alan Parsons Quadrophonic mix is to enjoy it to its fullest… :wink:

Playing the DVD, using an Oppo BDP-103EU into the Meridian does output 4.1, so I know it’s possible.

Any thoughts?

There is your problem. Since you ripped it, you could reformat it to 6channel 5.1 with a silent center channel.

@mitr (thanks for the response).
I was wondering if that was possible - but how do I do that?

I have the DVD-A which has been ripped with DVD-Audio-Extractor & only shows that it’s a 5-channel 96/24 source file (on the disc) and then rips to a 5-channel FLAC file, but I don’t know how it formats the file to show this crucial information. I don’t see the relevant information in the metadata when I use MediaMonkey - or how to modify the data.

Which other tools are available for checking the FLAC file ‘construction’ / metadata & can be used to change 5.0 to 4.1 or to 5.1?
And wouldn’t adding a ‘silent’ channel actually necessitate adding data - an ‘empty’ channel stream?

Also, my Oppo can clearly send a 4.1 stream (perhaps including some phantom or ‘empty’ channels) through to my 861v8, so I know it’s possible & works…somehow…

The question remains however: @support why does Roon down-mix the 5.0 (or 5.1 or whatever) stream to 2.0 when I explicitly tell it not to?

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@mitr
Thanks very much for the link to that software - extremely useful!

I’ve downloaded it, added a Centre Channel, but no joy… :thinking:

Why not?
I’ve found the answer - I appear to have asked the ‘same’ question before in 2017 on the Meridian HitchHikers forum - and worked out the reason why… :flushed:

The ID41 input card (which is what Roon ‘sees’) is 2-channel as is another connected device - my Meridian 218.
The answer is therefore to play this file through my Roon Core (i7 NUC) over HDMI into the multi-channel UHD722 and onward into the 861v8. :woozy_face:

Off to give it a try, although I’m pretty sure I’ve been through this loop before… :zipper_mouth_face:

Hi @John, was this channel mapping issue ever resolved?

I’m considering the Okto DAC8 @mitr mentioned and would want to be able to use bass management and other DSP operations with 5.0 files.

Thanks!

No. I have never received any reply after they acknowledged the issue.

I’m sorry to hear that.

@John, you wrote that a feature request ticket had been opened, but as I understand the reported issue, it’s a matter of getting a supported format to play correctly rather than adding new functionality. Any update on whether/when this fix might happen?