Question about Multi-Channel speaker placement

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Cygnus_X1

Active Member
Joined
Mar 3, 2013
Messages
62
Location
Los Angeles
Hello,
I've done a ton of research but I can't figure this out. I have an Acura MDX which I play 5.1 FLAC files through USB and they sound great.
I've been converting DTS 5.1 files to FLAC to listen in the car, but I notice the channels looks a little different.
Normally files are 3F2R/LFE, which is 3 front, 2 rear, and LFE for the sub. That's how Acura demo files are setup and most professionally mixed 5.1 files.
When I look at the DTS files and convert them to FLAC with VLC Media Player, I notice all the files are 3F2M/LFE, which I assume is 3 front, 2 middle, and LFE for the sub.
That seems more like a 7.1 setup using the middle channels and not the rear channels. I'm not sure if that makes any difference on how a 5.1 system handles the middle channels. To me, they don't sound as good in my MDX.
Also, does anyone know of an easy to use software I can use to change the channels around from side to rear? I'd be willing to buy something like JRiver Media Center if it would work.
Thanks.
 
Oh yes so he did...

I don't think I've tried using VLC Player to perform any type of encoding, maybe it's getting the channel assignments mixed up. In the past I have used software's such as UsEac3to or LameXP, or even FFmpeg. It's a shame his vehicle doesn't support native dts bitstreams.

That being said, @Cygnus_X1 have you tried muxing these .dts bitstreams into the .mka container. What audio containers does the player in your Acura MDX support?
 
From what I understand is that somewhere along the way the standard got changed. Channels once were (as you say) as follows Front Left, Front Right, Front Centre, Lfe, (Surround) Back Left and (Surround) Back right. Adobe Audition 3, which I still use has a "Matrix Mixer" which codes the channels that way.

Somewhere along the way things got changed so that you find now the surround channels are being coded a side rather than back. I use "Matrix Mixer" in Foobar to "correct" the channel assignments. Depending on what you are playing the files back on, reassignment of channels may or may not be necessary.

This is how to set up "Matrix Mixer" in Foobar to reassign side to back. Note that non intuitively the outputs are the channels shown vertically on the right side, while the inputs are across the top.

1730034912544.png
 
Thanks for the reply guys.

To answer some of the questions, my 2013 Acura TL would support DTS-CD and DVD-Audio discs. The newer Acuras, like my 2022 MDX, don't have optical drives anymore (USB only) and don't support DTS.

The types of files that can be played are fairly extensive, including mp3, FLAC, and wav, with support for 5.1 flac files. I have a ton of DVD-A discs and DTS CD's I purchased but I'm too busy (and lazy) to convert them all. I'm downloading DTS files from Usenet and converting them to FLAC using VLC. Interestingly, I converted a bunch last night and VLC seemed to switch most of them from 3F2M/LFE to 3F2R/LFE on it's own. I'm not sure why sometimes it works and sometimes not.

The 3F2M/LFE files do play in my Acura, but they don't sound the same as 3F2R/LFE. The rear channels seem to be playing the same thing as the front channels.

There is a setting in VLC to "Keep original audio track" when converting DTS to FLAC, but I think it encapsulates the DTS file in the FLAC file so it won't play in my Acura. I'm not sure if that's what SMD is referring to as muxing the .dts bitstreams into the .mka container. It only works if I do a full conversion.

par4ken, I like the look of that Foobar Matrix Mixer, I'm gonna try that and see how it works.
 
I find it useful to check the properties of the audio files in Windows. Checking Audio Properties you can see the number of channels and the channel assignment. Channel assignment is not shown for flac but is for wav. For that reason I usually like to save the files as wav first then verify the properties, if all is well save as flac.
 
I find it useful to check the properties of the audio files in Windows. Checking Audio Properties you can see the number of channels and the channel assignment. Channel assignment is not shown for flac but is for wav. For that reason I usually like to save the files as wav first then verify the properties, if all is well save as flac.
If you haven't already, you might want to try an application called MediaInfo, which needs to set to text mode.

Examples:
Capture.JPG


Capture.JPG
 
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Out of interest... What happens when you try to play this 'DTS Channel Check.mka' sample: -
I tried that mka file but my Acura doesn't even see it. VLC on my computer plays it just fine.
I do use MediaInfo to double check the files, just to make sure the channels match what is shown in VLC.
Below is a list from Acura of all supported audio types.
On a side note, one thing that drives me nuts about my Acura is that it will see the data tags like song name, artist name, album name, and even the album cover, but it refuses to acknowledge the track numbers. I have to prepend each song title with 01, 02, etc to get songs to play in the correct order, otherwise they play in alphabetical order. Even my 2013 Acura would read the track numbers. Oh well, first world problems.
I'm just happy that VLC seems to be working correctly now by changing the mid channels to rear channels on it's own. Maybe I flicked a switch somewhere in the software without knowing. Thanks for all the help guys.
Supported Audio Files.png
 
Okay... Here's a '6Ch AAC-LC Channel Check.m4a' sample: -
That file did play in my Acura and I could hear all the separate channels.
One odd thing though, the LFE channel came through the subwoofer and the front center speaker. I'm not sure if that's an error in my audio system or if it's mixed that way.
I'd be curious to see how it looks in that Foobar Matrix Mixer plugin recommended by par4ken, but I can't seem to get it to install correctly.
 
Does the matrix mixer work with the x64 version of Foobar? I pretty much quit using the 32 bit version this year.
I'm not sure but I think likely not. They say to use updated components with the 64bit version. Matrix Mixer is from 2008. I would try it anyway to see what happens.

Edit: It only works with the 32bit version. With the 64bit version it show up as "component not loaded". I have the 64bit version of Foobar installed as well but don't use it as many of the most important (to me) add on functions do not work, i.e. SACD.
 
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