Making Quadraphonic and 5.1 files for music server

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quicksrt

2K Club - QQ Super Nova
Since 2002/2003
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I have a basic question. If I record a poly wav say quad or even more channels I assume that going for the correct order to begin with locks in and if all goes as planned the channel assignment will be correct during playback if one goes in this order.

1. Front Left
2. Front Right
3. Rear Left
4. Rear Right
5. Center
6. Sub

I could then convert a 4-chan wav to FLAC, and JRiver for instance can figure out that this is quad and will know the drill as 1-4 of my list? Is it really that easy.

I plan on recording that Yen Years After - A Space in Time DVD, and correcting the F & B channel mixup. Then encode to flac for computer music server. No DVD authoring just file encoding.
 
I converted all my multichannel disc over to FLAC for PC playback.

The correct 5.1 channel assignment is as follows:
1. Front Left
2. Front Right
3. Center
4. Sub
5. Rear Left
6. Rear Right

When converting quad (4.0) to FLAC the channel assignment is as follows:
1. Front Left
2. Front Right
3. Rear Left
4. Rear Right
 
I have a document called "Recommendations For Surround Sound Mixing" which I found floating around the web, and it gives a number of specifications including channel allocation. Here it refers to a mix bus assignment. This is a direct quote from the document:

Bus-to-channel allocation should be as follows:
1 = L,
2 = R,
3 = C,
4 = LFE,
5 = Ls,
6 = Rs.
Tracks of a 5.1 master should be printed identically to the bus allocations.

I would be curious to see if the DSD and other HiRes multichannel downloads currently on offer conform to this (or indeed any) layout.

Brian?????

Here is the document: http://www2.grammy.com/pdfs/recording_academy/producers_and_engineers/5_1_rec.pdf
 
I converted all my multichannel disc over to FLAC for PC playback.

The correct 5.1 channel assignment is as follows:
1. Front Left
2. Front Right
3. Center
4. Sub
5. Rear Left
6. Rear Right

When converting quad (4.0) to FLAC the channel assignment is as follows:
1. Front Left
2. Front Right
3. Rear Left
4. Rear Right

For compatibility would you not want to encode quads as:

1. Front Left
2. Front Right
3. Silent
4. Silent
5. Rear Left
6. Rear Right

?
 
I have a basic question. If I record a poly wav say quad or even more channels I assume that going for the correct order to begin with locks in and if all goes as planned the channel assignment will be correct during playback if one goes in this order.

1. Front Left
2. Front Right
3. Rear Left
4. Rear Right
5. Center
6. Sub

I could then convert a 4-chan wav to FLAC, and JRiver for instance can figure out that this is quad and will know the drill as 1-4 of my list? Is it really that easy.

I plan on recording that Yen Years After - A Space in Time DVD, and correcting the F & B channel mixup. Then encode to flac for computer music server. No DVD authoring just file encoding.

There are different formats for channel order for surround files (which is likely the root cause of the faux pas on that TYA DVD).
The SMPTE standard (L R C Lfe Ls Rs) has become the standard and this is the channel order all computer media players and all hardware disc players will expect.
That's:
1. Front Left
2. Front Right
3. Center
4. Sub
5. Rear Left
6. Rear Right


FYI, on the computer you can change the channel order to whatever you wish with your OS utility. Audio MIDI Setup (OSX) lets you assign the surround outputs to the speaker channels as you please. (I'm not sure if the Windows audio utility - ASIO4ALL - does this but it likely has the same features.)

Also, the media player Songbird will play all formats out the correct speakers with your system set to 5.1 surround. Mix and match stereo, 4.0, 5.1, whatever.whatever, and everything comes out the correct speakers. Some other apps make you change Audio MIDI Setup for every format (switch between 4.0 & 5.1 for example).

There's also a free app available called Wave Agent that will let you reorder channels and rewrite the interleaved file. Or you can just use your favorite DAW app of course if you're up to speed with that.

For compatibility would you not want to encode quads as:

1. Front Left
2. Front Right
3. Silent
4. Silent
5. Rear Left
6. Rear Right

?

You CAN do that and it WILL prevent incorrect playback on either buggy or incorrectly setup apps.

I've seen official releases do this before as well.

Further, the FLAC format reduces blank (ie. digital zero) tracks to almost nothing, so it won't even use any more space to do this.
 
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The flac file format will hold data that identifies channel assignment. For example, you can rip a quad dvd-a to 4 channel wav/flac that will not have silent center sub info and put the rears in 3/4, which will playback properly on equipment that identifies the channel id. However, I'm not sure how to set this if manually saving a multichannel file from software such as sound forge, but there's probably a way. But one thing to keep in mind is that I have run into at least one piece of hardware that ignored the file's channel id and defaulted the 3/4 to the center/sub...but that box was a piece of shit that had many other problems.
 
Thank you. interesting stuff that more professionals should think about.

I am going to record the TYA output at analog. I want to get used to this recorder anyway rather than rip the streams from the Video_TS folder.

So to the experts here, do you think I should use the 5.1 layout for this 4.0 quad program, and for all my 4-chan stuff I do forever and here on out for consistency sake? Or go just for the 4-chan quad poly wav way?

Since the FLAC will be about the same size using the 5.1 layout why not? Or just sticking to 4.0 during recording is the normal way to go since I am not authoring a disc?
 
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Personally, I'd rip it, may as well stay in the digital realm. Find something analog that needs to be recorded in if you want to deal with the recorder.

When I was dealing with a device that was defaulting to a 5.1 layout, I was creating all my flacs with empty center and sub. But, I disliked the wastefulness of that. Once I determined 4.0 flac was possible, and that in my experience it was only garbage equipment that didn't read the files properly, I started creating 4.0 flacs for my quad materials. When you're ripping from digital sources that don't require correction, that's what they want to make anyways, so it saved me the trouble of manually converting 4.0 to 5.1 with empty sub and lfe channels.

The problem is, I don't know how to manually create 4.0 wave or flac files, which will be an issue for the TYA since you'll want to open those in an editing program and fix the front/rear swap. What I've been doing to get 4.0 flac is authoring a disc version of my conversions first, and then ripping the dvd-a portion to .wav, which results in a 4.0 wave with proper channel identification, which converts to 4.0 flac. I'm not sure how to bypass that part of the process if you don't want to author a disc.

What I really need to figure out is, how do you assign channel id when saving multichannel wave in audio editing programs such as sound forge? Anyone else have an answer to that question?
 
Personally, I'd rip it, may as well stay in the digital realm. Find something analog that needs to be recorded in if you want to deal with the recorder.

When I was dealing with a device that was defaulting to a 5.1 layout, I was creating all my flacs with empty center and sub. But, I disliked the wastefulness of that. Once I determined 4.0 flac was possible, and that in my experience it was only garbage equipment that didn't read the files properly, I started creating 4.0 flacs for my quad materials. When you're ripping from digital sources that don't require correction, that's what they want to make anyways, so it saved me the trouble of manually converting 4.0 to 5.1 with empty sub and lfe channels.

The problem is, I don't know how to manually create 4.0 wave or flac files, which will be an issue for the TYA since you'll want to open those in an editing program and fix the front/rear swap. What I've been doing to get 4.0 flac is authoring a disc version of my conversions first, and then ripping the dvd-a portion to .wav, which results in a 4.0 wave with proper channel identification, which converts to 4.0 flac. I'm not sure how to bypass that part of the process if you don't want to author a disc.

What I really need to figure out is, how do you assign channel id when saving multichannel wave in audio editing programs such as sound forge? Anyone else have an answer to that question?

I'm sure one of the many programs like DVD Audio Exployer will open a disc and let you explore it and grab the streams one wishes to obtain. It should be just as easy (for you experts) to open an ISO or a Video_TS folder and grab the audio streams, no? A friend of mine is doing it, but had some issues with certian but not all ISOs.

"how do you assign channel id when saving multichannel wave in audio editing programs? This was my original question, and I though the answer is to place the tracks in their correct order in the track list the way Ten Years After DVD producer was not able to do correctly, is that not enough?

In order to place them in the track order correctly I do cut and paste if I use Goldwave. I could copy track 1. FL and paste it in track 3. where RL currently is. And paste the contents on 3. RL into 1. FL. The issue as I see it is that one needs an extra track to hold a misassigned track when you are over-writing the bad channel with the correct one in that slot, so you have it to work with in a few moments.

If I am using a video editor like Sony Vegas or Final Cut Pro, then the tracks can easily be drag and dropped into their correct order.

Is there another thing you are referring to about "channel id", and not simply getting the wav in correct order 1,2,3,4, etc? Because I thought that getting correct order of a quad wav, and converting that to FLAC is all that was needed. And "copy and paste" or "drag and drop" were the two ways to do it in a audio editor.

Tell us if there is more to it called channel ID. I think you must mean "embedded" channel assignment.
 
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I would be curious to see if the DSD and other HiRes multichannel downloads currently on offer conform to this (or indeed any) layout.
All the DSD downloads I have do conform to this but 4 channel may sometimes present a complication. Using JRiver, I have found that one needs to specify that playback format is 5.1 or 7.1 to have consistent results. If one specifies playback format as "source number of channels," the Ls/Rs are played through the C/LFE outputs.
 
Not all audio codecs appear to support a 4.0 channel layout. I use Foobar2000 to convert my multichannel disc titles to either WAV or FLAC files. I currently use Windows Media Center as a front end media player and transcode the FLAC files to WMA lossless using dBpoweramp Music Converter. Windows Media Center supports FLAC with a plug-in however I have had issues with it. The WMA codec only appears to support 2.0 or 5.1 channel layouts, however dBPoweramp offers a channel mapping DSP that enables mapping the channels to the 5.1 standard. Most multi-channel SACD titles have either a 5.1, 5.0 or 4.1 configuration (straight quad transfers are usually 5.0 with a silent center channel). With Windows Media Center not being supported after Windows 8.1 I plan to switch to a different front end media player when upgrading to Windows 10 and will store my music library in FLAC format instead of WMA lossless.
 
FYI:
If like me you have a proper quadraphonic setup with four full sized speakers in the corners and nothing else (i.e. no center speaker and no sub) you will have a problem playing music 5.1 files that use the center speaker. Vocals will get lost etc.

An easy way to fix this is to downmix the 5.1 files to quad format. On linux I use the magnificent ffmpeg:
Code:
~> ffmpeg -i input.wav -af "pan=quad|c0<c0+c2|c1<c1+c2|c2=c4|c3=c5" output.flac
which downmixes the center channel to the 2 front speakers and writes a 4-channel flac as a result.

BTW. I discard the sub data because tests that I have done show no benefit when it is included in the output.

Regards,

-Philip.
 
This is a great thread to reference for those making .flac files for their music servers from their Chicago Quadio discs. I actually had the same question myself and wondered if I had to convert the 4channel ripped .flac files to 6 channel .flac files leaving the center and sub empty in order to play them with my Oppo without using the BluRay. Since they are 24/192 they are big and they take a lot of time to process and recreate even with a fast PC.
 
Uh... I don't really understand most of this thread, but I ripped the Chicago Quad layers to 24x192 .flac with Audiomuxer, and when I playback the files through my OPPO 103, they sound perfect, and exactly the same as when I play the discs. I have all my speakers set to "large" (because they are:)) and don't use any bass management. The subwoofer never turns on when I play these Chicago quads.
 
This is a great thread to reference for those making .flac files for their music servers from their Chicago Quadio discs. I actually had the same question myself and wondered if I had to convert the 4channel ripped .flac files to 6 channel .flac files leaving the center and sub empty in order to play them with my Oppo without using the BluRay. Since they are 24/192 they are big and they take a lot of time to process and recreate even with a fast PC.

I use J River 21 and had to convert the Chicago Quadio from 4.0 to 5.1 using Audiomuxer (with C and LFE empty) in order to get the 4 speakers playing properly - the initial 4.0 would play in FL, FR, C, and LFE..
 
I use J River 21 and had to convert the Chicago Quadio from 4.0 to 5.1 using Audiomuxer (with C and LFE empty) in order to get the 4 speakers playing properly - the initial 4.0 would play in FL, FR, C, and LFE..

I'm surprised J River 21 cannot correctly play Quad. Can you upgrade or find a media player that does use correct channel mappings?

A mate of mine has an old Western Digital media player that cannot play anything other than 5.1 correctly. So 4.0, 4.1, 5.0 etc plays with wrong speakers assignments. Apart from many quad releases this rules out most classical MCH releases too (5.0).
 
I just did most of the Chicago Quadio box using MakeMKV and then AudioMuxer (Extract Audio from MKV file) and I got perfect 24/192 4 channel .flac files with proper cue's and they play perfectly from a USB drive connected to my Oppo. No channel futzing required. Works great.
 
I'm surprised J River 21 cannot correctly play Quad. Can you upgrade or find a media player that does use correct channel mappings?

A mate of mine has an old Western Digital media player that cannot play anything other than 5.1 correctly. So 4.0, 4.1, 5.0 etc plays with wrong speakers assignments. Apart from many quad releases this rules out most classical MCH releases too (5.0).

VLC does this on my Macs, too.. you have to have a silent/blank Centre (3) & LFE (4), so Quad's are mapped as 5.1 rather than 4.0, otherwise you get the 2 x Rear channels popping up in Centre & LFE respectively (with as you can imagine yucky sucky surround results!) its a PITA! :D
 
I'm surprised J River 21 cannot correctly play Quad. Can you upgrade or find a media player that does use correct channel mappings?

A mate of mine has an old Western Digital media player that cannot play anything other than 5.1 correctly. So 4.0, 4.1, 5.0 etc plays with wrong speakers assignments. Apart from many quad releases this rules out most classical MCH releases too (5.0).

You can in JRiver set the output to be 5.1 - this will take a 4.0 and upmix it to 5.1, - it creates an actual C and LFE, and then the Ls and Rs do play in the proper speakers..
 
You can in JRiver set the output to be 5.1 - this will take a 4.0 and upmix it to 5.1, - it creates an actual C and LFE, and then the Ls and Rs do play in the proper speakers..

Not necessarily. If you play a quad with JRiver set to output 5.1, you have a separate option that lets you decide whether it will create/synthesize "an actual C and LFE" or not. In the latter case, which I use, JRiver does not create anything but simply redistributes the 4 channels so that, indeed, "the Ls and Rs do play in the proper speakers."
 
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