What goes on Dialog Track stem & What goes on Effects track?

When making stems for a film, and there is the sound of a car driving up and someone talking right after the car pulls up: Does the sound of the car go on to the “effects” stem or does it stay on the dialog track?

I guess my question is this: the sound of the car should not be in both the “effects” & “dialog” stems correct?


The sound of the car should be in the fx stem as it is an fx, but is not very important as soon as you know where is it and how you are going to mix it

The thing you have to keep in mind is that if the car and dialog are at the same time could be okay for the original version if ADR is not possible, but you will have to recreate the car for the M+E (music+fx) mix as when you remove the dialog for dubbing the car will be removed also.


So wait; do you replace any and all sounds that occur in the dialog track on the M+E as well? Surely that must depend on the specs though, right? Because if the client wishes to use the stems for adjusting the full mix rather than replace dialog (new language etc), they’d end up with two car sounds, yes?

Or am I misunderstanding something?

Also, how would background noise be mixed since you’d have to do cover nat in the dialog track when the car is sounding (since it’s now moved to an fx track instead)? Because you need consistent a background sound in the dialog track, and then when the split out car is playing you’ll hear the background sound from it too, so they “add up”. If it was a door slam I’d split it out no doubt (to PFX) and wouldn’t consider whatever noise is on that little slam to be a problem, but a car pass is a bit longer in duration so…

The comments highlight the two extremes of how Post is done.

On the one side there is the -what I call- “damage control”.
The Audio Post Studio “fills” up anything that is missing from the location sound, in order to obtain a consistent audio “stream” throughout the movie/series.

In this case the client should be very aware of the limitations of this method. Delivering an M&E for dubbing in another country is simply out of the question. (Actually, we are building a good business on building M&E tracks for Tv series which are sold to a foreign country.) For Sunshy this means leaving the DX track untouched, and just adding what’s missing. Of course that limits the mix- and many more compromises need to be made.

On the other hand, there is the “High Quality” Movie-way_of_doing_things. Which means that everything is “re-done”. So, as soon as you mute the dialog track, the whole M&E track completely stands up and is complete/ready for foreign language dubbing. This involves splitting up the location sound into a PFX, BG and Dialog track, and then later “fill” anything that is missing. For Sunshy this means, replacing the car and performing ADR on the dialog. This procedure also gives more mix options.

And there is everything inbetween. As for how to approach it, whatever works best for you. But you need to be sure that you are in agreement with the client, that he is aware of the consequences and limitations. Otherwise you will be in big trouble. As for us, even for “damage control” series, we put in many extra work for splitting everything up into different stems, even though some parts will be missing. The advantage is that it results in a much cleaner project, easy to mix, easy to find stuff, and whenever an M&E needs to be build at a later time, you are already halfway. That is our personal “investment” in each project.


I think Fredo is spot on.

I’d just emphasize that the biggest factor to determine how you should do this is how much money the client wants to spend. The difference between a “full-on movie-edit” and a “just-make-it-work” edit is significant. Pulling out all usable sounds from the dialog track and putting them on a PFX track, cutting up the actual dialog, replacing all cases where dialog and fx coincide (the passing car) with ADR and effects from elsewhere… it’s all quite time-consuming.

Like others said; check with your client and make sure you both know exactly what you’ll deliver at the end of the project.

Thanks for clarifying my post. I couldn´t explain it better.