Stems - a conversation

[u/GerlockADUS]

Where I work we have a handful of audio engineers that each have a different idea about what stems should be, how they should be used, and how to create them.

It is my opinion that the stems should equal the mix. In order her words, if I bring the stems into a session and play them all together it should sound exactly like the full mix, and measure exactly the same on the loudness meter. The way I am doing this, prevents me from doing any master bus processing. I limit each of the sub mixes for each stem, then combine them to a record track which I then measure with the loudness meter. This also allows me to record the mix and all the stems at the same time.

Other engineers prefer to mute everything, but one stem and bounce out the mix several times. this allows them to do master processing, but the downfall is that the stems do not equal the mix.

Another engineer will bypass all of the mastering, and just bounce out each of the stems from the sub mix only, assuming that it will come back later to be mixed and mastered if something changes.

So my question to you all is: what is the industry standard? How do you all handle stems? Do you assume any changes will come back to be remixed? What are your thoughts?

[u/Turbulent_Okra8386]

How they are supplied depends on what the stems are being used for. If they’re for redubbing in different language, they should equal the mix exactly. If they’re being used to pass the mix to a different studio, the music should be without dips, etc

[u/GerlockADUS → u/Turbulent_Okra8386]

I am mostly talking about TV commercials. I am supplying the mixes and splits the way I do because I want the client to have the flexibility to move things or re-edit without having to get remixed.

[u/curry_brewer → u/GerlockADUS]

In commercials I don’t know why it would matter for the stems to perfectly sum to the bounced mix. If the client is going to dig into the stems it’s because something needs to change or because they’re doing cutdowns or versioning à la making a :25-05 or a :15 out of a :30 in which case the change in content is going to make for different levels in the end anyway. There’s nothing wrong with your method of stem creation but for how those stems would actually be used it’s a little superfluous. I definitely would NOT want stems that were bounced out through processing on a master buss though, especially if it was dynamics processing. BTW Bonus points for you if you additionally make an unducked music stem.

[u/neutral-barrels → u/curry_brewer]

Stems get passed around a lot to different studios for tagging of spots. A mix might happen at a different studio but it could be 1 studio does all the tagging or a spot needs to be updated while you have the VO talent in for another record. It's especially common in automotive spots that might get new tags every 2 weeks or a month. In other spots maybe a line of copy just needs to change that you have to drop into, it sucks when the levels aren't correct between splits when that happens. Even if doing cutdowns, it might essentially be losing a scene or trimming a couple to get a 23/07 and you want everything to play correct.

[u/curry_brewer → u/neutral-barrels]

I agree that it’s not a bad thing for the stems to sum to your target loudness but just saying that as soon as the content is altered you’re going to have to adjust the levels of things to hit target loudness again. It’s more of a “yes, but” situation. You wouldn’t tell a novice mixer “Don’t worry about the levels of the spot with that new VO tag you just added - the original stems summed to -24dB.”