Music replacement and surround sound...

[futon88]

If your intent is to replace music and all you have is a stereo .mp3 or .flac, how do you go about adding it to the mix in a way that matches how a traditional score is mixed in? If you were to simply drop an .mp3 into your NLE, would the music placement be incorrect?

I've been working with the assumption that the music needs to be mixed into FL, FR, BL, and BR, but I'm not sure if that's true.

This is what I'm doing:

• Open .mp3 in Audacity
• Split stereo track to four mono tracks
• Rename as FL, FR, BL, BR to keep things clear
• Reduce gain slightly on BL and BR.
• Export as six channel .wav, mapping to 1, 2, 5, 6

Is that completely bonkers?

 

[DigModiFicaTion]

Is that completely bonkers?

I mean, that's not how I would do it, but I wouldn't call you bonkers. What NLE are you using?

You probably don't need to create the separate tracks. If you create an LFE track, the music will be bassed out. Generally, you can use the same track and process it to match the surround mix (more fully sounding up front, more muted in the back, frequency differences etc.)

In Vegas, you can create a new audio track and drop the music file in. Then you can map it to where you want. Sometimes I'll drop the music file in and move the surround space forward, but not to the full front. This puts the music mostly in the front, but it will also bleed into the back. I then do some volume adjustment to make it fit in the mix and add any vfx processing as necessary. Some movies have the music in the front and the back, if that's the case, this method works. If that's not the case, then you'd want to create a front channel (move the surround track placement to the full front). There's no one way to do it, but you'll need to do a lot of A/B-ing with your source audio tracks to best match the levels and sound of the mix.

 

[futon88]

My NLE (flowblade) doesn't support this type of audio editing, but I can map it how I want in audacity and it will honour that mix when it renders.

It sounds like I should adjust my process slightly: I should map an LFE channel too (#4), and presumably run it through a low pass filter. If that's correct, what frequency cut off would you suggest?

 

[DigModiFicaTion]

I'd recommend not doing a music LFE. You'll have plenty of bass from the other channels. The LFE channel is essentially for "big boom" scenes. I'd recommend using a different NLE if yours doesn't easily allow for sound mapping. Not much worse than a vision/plan and tools that don't allow you to accomplish your goals.

 

[korach1921]

Is it recommended to also downmix the stereo music to a mono track to put in the center channel (at a much lower volume)? That's what I'm trying to do

 

[korach1921]

Oh wait, I read this thread incorrectly, nevermind

 

[DigModiFicaTion]

Is it recommended to also downmix the stereo music to a mono track to put in the center channel (at a much lower volume)? That's what I'm trying to do

Depends on what your NLE is capable of doing. In Vegas it allows you to select which channel you want to use, so you don't need to separate the track into mono files.

 

[korach1921]

Depends on what your NLE is capable of doing. In Vegas it allows you to select which channel you want to use, so you don't need to separate the track into mono files.

I'm using Davinci Resolve. Do you know if Fairlight is comparable to Vegas at all?

 

[DigModiFicaTion]

I don't. I've tried a lot of NLE's and for me Vegas has the best audio interface I've found. That's why I stick with it. The tracks are easy to input and edit. DaVinci Resolve is free and very comprehensive. I just haven't had a reason to switch to it from Vegas.