Clarification for 5.1 audio

I would be grateful if you could advise me on the best path to follow.

The 5.1 procedure for creating a DCP for cinema is to have six separate, mono channels, insert them into the timeline in the right order...

In the Fairlight Page select all 6 mono audio tracks. In the DaVinci Resolve menu bar, click “Fairlight” and then “Link Group…”. In the window that pops up, select all 6 mono audio tracks (A1 – A6) and click on "Link as..." 5.1in the lower right corner.

In the DaVinci Resolve menu bar, click “Fairlight” and then “Bus Format…” In the window that now pops up, click on “Add Bus”. For the newly added Bus under "Format" choose “5.1”. Press "OK" in the lower right corner to close the window.

etc. etc.

My problem is that I'm mixing with 26 audio tracks.
Therefore I had first thought of doing the mix and exporting the six mono tracks, then re-importing the six tracks following the procedure described above.
But it creates a problem.
For fx channels I have 10 tracks. Take a shooting scene for example. If I have two tracks with bullets coming from the rear right channel, two tracks coming from the front left, two tracks with bullets coming from the front right etc... when I export the mono files of the two individual channels, I will necessarily have to merge all in two channels, so I will necessarily find the sound of superimposed bullets not separately (front left, rear left for example). When I import the mono channels for the creation of 5.1 I will no longer be able to separate sounds of bullets that went to the front and others that exploded at the same time that went to the rear because they are mixed together. The ideal would have been to be able to mix in surround and export the 5.1 directly from the timeline with the 26 audio tracks, so you could assign every single sound to the right channel. So I wonder if it is possible to do the mixing in 5.1, then export the audio of the bus assigned to 5.1. Re-import the exported audio, create the six mono tracks, insert the 5.1 audio file into each single mono channel (choosing the channel corresponding to the correct audio track from the audio properties) and then proceed with the procedure for 5.1 described above.
The first question is: can it be done? What do you recommend?

Configure the 5.1 Bus as the Output Track on the Deliver page's Audio tab for outputting the DCP.

Create Busses for each stem and either configure multiple Output Tracks via the Deliver page or Bounce Mix to Track to output individual stems and include stems on the current Timeline.

If importing stems or source channels for authoring in a different session or Timeline, the Link Group automatically provides appropriate channel mapping - there is no need for manual mapping.

Configure the 5.1 Bus as the Output Track on the Deliver page's Audio tab for outputting the DCP.

Create Busses for each stem and either configure multiple Output Tracks via the Deliver page or Bounce Mix to Track to output individual stems and include stems on the current Timeline.

If importing stems or source channels for authoring in a different session or Timeline, the Link Group automatically provides appropriate channel mapping - there is no need for manual mapping.

First of all, thank you for the reply.


I have the first step clear, this:
Set up the 5.1 bus as the output track on the Audio tab of the Delivery page for DCP output.

I didn't quite understand what to do next. If I already export the DCP and configure the 5.1 Bus as the Output Track on the Deliver page, shouldn't I already have the DCP with 5.1 audio? Can I ask you to kindly explain the next steps to me?

If I already export the DCP and configure the 5.1 Bus as the Output Track on the Deliver page, shouldn't I already have the DCP with 5.1 audio?

Correct. If the 5.1 Bus is defined as the Output Track the DCP will include source channels with correct mapping.

If I already export the DCP and configure the 5.1 Bus as the Output Track on the Deliver page, shouldn't I already have the DCP with 5.1 audio?

Correct. If the 5.1 Bus is defined as the Output Track the DCP will include source channels with correct mapping.

So if I have a timeline with 26 audio tracks, I have created a 5.1 bus and I have done the correct mixing for 5.1, I can export directly by choosing the 5.1 bus as audio output without having to export 6 mono tracks, re-import the six tracks, assign the six tracks etc etc?

Correct.

Correct.

Thank you very much, I don't know why some people were insisting that I should necessarily create six mono tracks.

Correct.

Thank you very much, I don't know why some people were insisting that I should necessarily create six mono tracks.

Well. I would still advise to do it that way.

I don't understand how doing it directly from your 26 tracks would avoid the problem you described when having 6 mono tracks, since that's what the DCP will have, 6 mono tracks. So whatever issues your getting in Resolve, you'll get on your DCP.

I do see you talk about separating the bullets after importing the mono tracks, but these mono tracks should be treated as final mix deliveries and not used for further mixing.

Correct.

I wanted to ask you for another piece of advice. I moved only the Impact and strong Effects channels to the sub woofer.
Some also move the soundtrack to have deeper bass on the sub woofer channel. What do you think about it?
Another doubt concerns the sound coming out of the sub woofer. Basically I hear the sound the same as that of the other channels. Shouldn't only the low frequencies be heard? Maybe I have to insert a low pass filter in davinci resolve?

Is “Only” enabled in the Fairlight Panner or are you feeding full bandwidth audio to a Bus?

Fairlight includes the “LFE Filter” AFX which provides a low pass filter.

Correct.

Thank you very much, I don't know why some people were insisting that I should necessarily create six mono tracks.

Well. I would still advise to do it that way.

I don't understand how doing it directly from your 26 tracks would avoid the problem you described when having 6 mono tracks, since that's what the DCP will have, 6 mono tracks. So whatever issues your getting in Resolve, you'll get on your DCP.

I do see you talk about separating the bullets after importing the mono tracks, but these mono tracks should be treated as final mix deliveries and not used for further mixing.

Sorry I didn't read this answer.
I have 26 tracks because for each channel I have several tracks (for example six tracks for dialogues, 4 tracks for ambient audio, 8 tracks for fx etc.).
I went to Fairlight - bus format - and created a 5.1 bus.
Then I mixed each individual track using pan (moving the track's audio to the correct position). For example, if I have 8 tracks with audio FX going on the front left and right channels, I use pan to make these eight tracks play on the front right and front left channels. So even if there are eight tracks, all eight will play on the front right and front left channels. I do the same thing for all the other tracks, I move each track to the correct channel. I have for example three tracks for soundtracks. I set the pan of each of the three tracks 75% on the rear channels and 25% on the front channels.
This way it doesn't matter how many tracks you have, you can even have 200, but they will all play on the six 5.1 channels following the pan settings. I tried exporting a few seconds. From Deliver I set the 5.1 bus I had created as the audio output. I imported the audio back into Davinci and created a 5.1 audio track. I inserted the exported audio into the created track and it seems to work. There are 6 channels and each audio is on the right channel.
Am I doing something wrong?

Is “Only” enabled in the Fairlight Panner or are you feeding full bandwidth audio to a Bus?

Fairlight includes the “LFE Filter” AFX which provides a low pass filter.

I activated (by clicking on) the sub woofer from the fairlight audio pan of the fx track (where there are effects with deep bass) and set the volume to -3db. I expected to hear only the bass like in a system with a low pass filter, but instead it reproduces all frequencies like all other speakers.

Put the LFE filter into the filter slot of your 5.1. mix bus. That will provide a low pass filter to your LFE channel only.

As far as I understand, you're not doing anything wrong. Because of the way I'm used to working, I would separate the process even if it meant the extra render.

I should point out that I'm not a sound person and that always the final mix is delivered to me to import into Resolve.

I like working like this with my images as well, where my video track is a DPX or TIFF image sequence of all the color grade and vfx I've done. It can be big in terms of space but worth it in terms of speed and reliability... I know it's different for sound.