What Is Stem Mixing?
Over the last few years, it’s become standard procedure for artists, producers and engineers to print stems of their sessions in order to reduce track count, make it easier to overdub additional tracks, or collaborate with other musicians. But when you're looking at a session with over 100 tracks, it can seem overwhelming to narrow it down to just a few stereo tracks.
In this blog, you'll learn how to create stems to use for mixing and mastering, as well as some tips for working with stems. But first, let's talk about what stems actually are.
What Are Stems?
Most mixing projects are multitrack sessions, meaning there is a single track for each element of the mix. If there are three kick drum sounds, there will be different tracks for each sound—the same goes for every instrument in the song.
Stems combine one or more elements of a mix into a single stereo track. For instance, instead of having multiple channels for each kick, snare, tom and cymbal (not to mention overheads, room mics, and misc percussion), all of the drum tracks are summed to a single stereo Drum Stem.
While there are no hard and fast rules for creating stems, it's common to create stems for drums, bass, other instruments like guitars and synths, and vocals. Some people like to get more granular when making stems and use separate tracks for guitars and synths, while others group everything together under one umbrella.
Depending on the genre, some people even create separate stems for kicks and snares—especially if you're blending together multiple sounds or samples. Similarly, with large, vocal-driven sessions it's common to break out the lead vocals from the background vocals.
It’s about finding the balance between simplifying a project and keeping it flexible enough to make tweaks further down the line.
Now that you understand the difference between stems and multitrack sessions, let's talk about the benefits of stem mixing, and when to use this tried and tested technique.
Try Mixing Stems Yourself with Balancing Channels on Ultimate Producer
Benefits of Stem Mixing
There are lots of great reasons to start using stems when mixing your tracks, but perhaps the most compelling is that it simply makes sessions easier to manage. Whether you're mixing, mastering, remixing, or overdubbing, stems are a great way to save time in the studio. Stems make it easier to quickly tweak your mix, like adjusting the balance between two elements.
Stems are also great if you’re working with limited resources. For those of us who are still making beats on a laptop from the turn of the millennium, it can be tricky to run a session with lots of tracks or use any powerful plug-ins. By summing your tracks to stems, you can save resources by printing any processor-heavy effects, or applying them to the bus instead of per-channel.
Stems are especially useful when collaborating with other musicians and engineers, too. Stems make it easy to pass files to another artist or producer for a remix. They allow the remixer to keep what they like and change what they want, without having to recreate your mix from the ground up. This is a great way to make sure your vocal tracks retain the same professional polish as your official release.
Similarly, stems are essential if you want to license your music for TV or film. You'll need to provide instrumental and acapella versions of your track on-demand, which is much easier when working with stems.
Breaking your sessions down into stems can also be helpful when it comes time to play your music live. If you added a bunch of synths or extra guitar parts in the studio that you're not able to recreate live, you can use the stems as backing tracks for performances.
Finally, creating stems during the mixing stage will also give your mastering engineer more flexibility. This can be especially useful if you mix your tracks yourself and hire a professional mastering engineer to apply the final coat of polish. With stems, the mastering engineer is able to better adjust the balance between elements, or make adjustments to different instrument groups.
Now that you understand the benefits of using stems, let's talk about how to create stems for any session.
How to Prepare Mix Stems
The first step in creating stems is deciding how to group each of the instruments in the track. Do you want to use a simple four-track approach with drums, bass, instruments and vocals? Or should you print more detailed stems for kick, snare, guitars, synths, etc?
Remember, stems are just groups of instruments, and you can group the instruments however makes the most sense for your mix. You can disable any plug-ins that aren't essential to your sound, but be sure to include effects channels as well, such as drum reverb, vocal delays and parallel compression. The idea is to group all of the tracks that contribute to the overall sound of the instrument so you can quickly make adjustments to the group using a single channel.
It's also a good idea to listen closely to each stem to make sure there are no technical issues with any of the tracks. Make sure none of the tracks are clipping, listen closely for clicks or pops, remove any unwanted hiss or noise, and check for phase problems. This goes for problems with frequency response, too. If a track stands out as muddy or harsh compared to the others in the stem, bust out your favorite EQ and clean it up.
Obviously, it kind of defeats the purpose to EQ every track individual if you're going to be printing stems, but it's important to note that you won't be able to perform surgery on a single instrument when working with a stereo file. Trying to remove the muddiness or harshness from one track in the stem will affect all of the tracks, so unless all of the tracks have the same problem you'll wind up working in circles.
Once you’ve ironed out all of the kinks, spend some time getting the balance and panning right for all of the tracks in each stem. It's important to make sure that you can hear each instrument clearly, as you won't be able to make any changes after printing the stems.
How To Print Mix Stems
Once your stems are premixed and ready to start printing, solo the tracks you want to bounce. This will ensure that no other instruments accidentally get included in the wrong stems. Then, use your mouse to select the range from the very beginning of the track to the end of the last clip. This will ensure that all clips are the same length, and more importantly, that all clips start at the beginning of the session.
If you simply bounce or export the clips without selecting the full area of the track, your clips will not be consolidated, and will bounce from the beginning of each clip. It is an absolute nightmare trying to find the exact start point of each clip. Even if you're off by as little as a few ms, it can throw off the groove of the whole track.
You may also want to create fades at the beginning and end of each clip to help prevent any harsh pops or clicks caused by rough edits. Thankfully, most DAWs feature simple batch commands for adding fades to multiple clips simultaneously.
Repeat this process for all of the tracks in your session, until you've created stems for each group of instruments. Then, listen back to each stem to make sure no errors occurred during bouncing. It's common to accidentally leave a track muted or un-muted while bouncing stems, which is why it's important to make sure all of the files are accurate before beginning the mixing process.
Once you've printed all of the stems for your session, create a Google Doc or text file that includes all of the session information. Note the name of the song and the artist who performed it, along with technical details like the tempo, meter, sample rate, bit depth and file type for each stem.
Make sure all of the stems are labeled clearly and appropriately, then zip everything together in a folder to make it easy to share with others. Whether you're mixing the track yourself or passing it off to another engineer, the mixer can drag and drop the files into any DAW and everything should be labeled, lined up and ready to rock.
Tips For Mixing with Stems
After loading up a session of stems, you may be thinking "what do I do now?" It can feel a little limiting not being able to tweak each track in the mix, but it makes you think about how each of the elements interact with each other.
As opposed to carving up every track with a surgical EQ, listen to the stem and identify what it's contributing to the mix. Then, find a way to enhance that element of the track. It could be as simple as using shelf EQ for a little extra low-end or adding some shimmer to the high-end. Or it could be more complicated and require you to break out a multi-band compressor to fine-tune the dynamics of each frequency range.
No matter which approach you take, it's important to remember that stem mixing is all about bus processing. You have to consider what the plug-in will do to all of the tracks in the stem—not just one track that may be sticking out.
Start with soft, gentle settings and try to focus on how each of the stems interact with one another. You can also route all of the stems to a mix bus for an additional layer of processing. A little compression here can really help glue things together. Just be careful, as you're likely compressing the stems as well, and serial gain reduction adds up fast!
As always, be sure to check your mix on a variety of systems to ensure it's translating well. Once you're happy with the way your track sounds, you can either bounce it down to a standard two-track mix for traditional mastering, or simply print the processing on your stems and send them to a mastering engineer. Stem mastering gives the mastering engineer extra flexibility, and is a great option for artists who mix their own tracks.
Want to learn more about working with stems? Check out our blog on Mastering vs Stem Mastering: What's the Difference?