Surround Mixing using Ardour

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abhayadevs
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Hi, I am planning for a surround mixing for a video. Thinkig of using Ardour 2.x or 3.x (using 2.x for all my work but not sure 3.x is production safe).

My plan is th have 6 Buses for the L, C, R, LS, RS and LFE. and add sends from all my audio-fxs tracks to all the 5+1 surround buses and automate the send levels for the surround panning. Also put some HPF on LFE. Also planning to use ac3jack. This would help me to get the 5+1 tracks and i can use them while rendering the video in the 5.1 supported video editor. Anybody tried something like this? Please share your comments and tips....

seablade
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5.1 mixing, or most 'standard' mixing solutions are pretty difficult in Ardour to be honest. Yes I have done similar things, but it is rough, and personally it isn't my first choice.

If you do want to use Ardour, I would suggest a few things. First look at what tracks need to go where. Standard mixing for video places most vocals on the center channel, and FX on the outside as well as music for much of the video(Not all but much). LFE only gets used for certain things in general, almost never for voice, and really only on certain SFX in most cases. Simplify your routing as much as possible as a result.

Seablade

abhayadevs
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@seablade, thanks for the information.. so what is your favorite tool for this? Also, should I keep LFE untouched?

abhayadevs
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http://www.grammy.org/files/pages/SurroundRecommendations.pdf says,

There is no clear-cut answer, but the mere presence of the LFE channel almost
dictates that it be used. The danger lies in overuse, because too much reliance
on the LFE channel to carry bass information can result in the loss of low end
altogether on incorrectly configured or poorly designed home theater systems. In
addition, the LFE channel is discarded by most matrixed encoding systems (such
as Dolby Pro Logic; see section 1.1) and downmixing algorithms (see section
5.5), including those used for HDTV broadcast. Therefore, the LFE channel
should never be used to carry the bass content of the main speaker channels —
that is the job of bass management.

so its better to not to use the LFE...

seablade
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Short version of the above, LFE is intended to be used to give an extra 'oomph' to the bass on particular sounds. When mixing for 5.1 it is to be assumed that all 5 channels are full range in themselves. So only use the LFE when you 'need' to.

My favorite tool for this is just about any other mixing system that handles N.M style mixing better. You can do it in Ardour, and it is much easier in A3 than it was in A2 with at least basic semi-working surround panning in the VBAP panner, but that is not a be all end all answer to N.M mixes, not even close. In Ardour if/when I tackle this again, which is coming up soon I think, I will likely take a hybrid approach involving either ambisonics panning or VBAP, combined with direct sends as you mentioned above. At first thought, keeping in mind I haven't looked to closely yet, I will probably be looking to create template tracks for SFX that might be a VBAP panner to the outside speakers, with a send to the LFE, Vox tracks that would be routed to the Center, maybe with sends to the FL/FR in case I need to do panning entrances etc. and Music routed to L/R with sends to the rear, and surround verb routed to the outside speakers. Again I haven't thought about it much though and I caution you on taking this approach as it will still have some difficulties (For instance routing diagonally across the listening position) and I may use ambisonics instead but that could have other issues in as far as isolating soudns to specific speakers, etc. So no one size fits all solution here, sorry.

Seablade

abhayadevs
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i am just starting with A3 and may be i need to find out the VBAP and Ambisonic techniques. BTW, what is this N.M Style mixing?
Yeah your approach is also should be selectively applied.

seablade
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N.M is shorthand for standards like 5.1, 7.1, etc.

Seablade

paul
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the VBAP panner is basically useless as is (and certainly without documentation). sad to say.

abhayadevs
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https://community.ardour.org/node/7939