As a mastering engineer, I’ve worked on hundreds of projects using both stereo and stem mastering approaches. Recently, I decided to run an experiment: I took a track I’d already mixed and mastered for the band Red Moon and remastered it using stems to see if I could improve upon the original stereo master. The results were enlightening. Let me walk you through exactly what I did, what changed, and how you can decide which approach might be right for your next project.
Understanding the Fundamentals
What Is Stereo Mastering?
Stereo mastering is the industry standard – it’s what most artists are familiar with. You bounce your final mix as a stereo file from your DAW and send it to your mastering engineer. We then apply our processing chain to that single stereo file, enhancing the overall sound before it heads to streaming platforms.
This approach works brilliantly when you’re completely happy with your mix. It’s efficient, straightforward, and in most cases, delivers excellent results. I’d estimate that 80% of the projects I work on use this traditional approach, and for good reason – it works.
What Is Stem Mastering?
Stem mastering takes a different approach. Instead of working with one stereo file, I receive multiple stems – typically drums, bass, music (guitars, keys, etc.), and vocals. Sometimes clients send additional stems for specific elements they want more control over, but those four core groups are my standard request.
The key difference? I can now manipulate each element independently before applying the final mastering chain. Think of it like having a mixing console with just four faders instead of working with a single stereo track.
The Real-World Difference: A Case Study
Let me share what happened when I remastered Red Moon’s “Bad Days” using stems. The original stereo master I’d done months earlier sounded great – clean, balanced, with the vocals sitting nicely in the mix. But listening back, I heard opportunities for improvement that wouldn’t have been possible with just the stereo file.
The Drums
The snare was getting slightly over-limited in the original master. With access to the drum stem, I applied gentle clipping to control the transients without sacrificing punch. This might sound counterintuitive, but by slightly clipping the drums before they hit my final limiter, I preserved more of their natural impact. The difference? About 1.25dB boost at 5kHz gave the drums more presence without harshness.
The Music
The guitars felt slightly buried in the original master. Working with the music stem, I could enhance the stereo width with the Brainworx BX Digital EQ specifically on the sides (adding about .5dB at 11kHz on just the side information) while keeping the center clear for vocals. This created that wraparound effect where the guitars embrace the listener without cluttering the mix.
The Bass
Sometimes the smallest moves make the biggest difference. I boosted the bass stem by just 0.6dB. In mastering, these tiny adjustments can transform how a track feels without obviously changing its character.
The Vocals
A touch of de-essing was all that was needed. Certain sibilants were just slightly too prominent – something I couldn’t address in the stereo master without affecting the entire frequency spectrum.
When Should You Choose Stem Mastering?
Through my experience, here are the scenarios where stem mastering really shines:
Choose stem mastering when:
- You’re mixing in an untreated room and unsure about your low-end translation
- The mix sounds good but something feels slightly off that you can’t pinpoint
- You want a safety net for potential mix issues
- Different elements need different types of processing (e.g., drums need transient control while vocals need smoothing)
- You’re curious about alternative versions of your master
Stick with stereo mastering when:
- You’re completely happy with your mix balance
- Your mixing engineer has years of experience and a treated room
- You’re working with a trusted mixer whose work consistently translates well
- Budget or timeline constraints make the simpler approach more practical
The Technical Approach That Makes the Difference
In my workflow, I treat stem mastering as a hybrid between mixing and mastering. After processing individual stems, everything flows through my analog chain – a Bettermaker mastering EQ for those subtle frequency adjustments (often just 0.5dB moves at key frequencies), then back into the box for final limiting.
The magic happens in the accumulation of small moves. A half-decibel here, a touch of width there, some gentle transient control – individually, these adjustments are almost imperceptible. Together, they create a master that feels more alive, more three-dimensional.
The Bottom Line: It’s About Options, Not Superiority
After years of doing both, I’ve learned that neither approach is inherently superior. The best choice depends on your specific situation. Some of my favorite masters have been straight stereo files where everything was already perfect. Others have been stem masters where we discovered magic in the ability to fine-tune individual elements.
What matters most is understanding what each approach offers. Stereo mastering provides efficiency and cohesion when your mix is solid. Stem mastering offers flexibility and problem-solving capabilities when you need that extra level of control.
Your Next Steps
If you’re preparing for mastering, ask yourself:
- How confident am I in my mix?
- Are there any elements I wish I could adjust but can’t without affecting others?
- Would I benefit from a mastering engineer’s perspective on individual mix elements?
If you answered “very confident,” “no,” and “not really,” stereo mastering is probably your best bet. Any uncertainty in those answers might make stem mastering worth considering.
Remember, the goal isn’t to fix a bad mix in mastering – it’s to elevate a good mix to its full potential. Whether that happens through stereo or stem mastering is less important than choosing the approach that serves your music best.
About the author: I’m a professional mixing and mastering engineer working with independent artists and bands to help their music compete at professional levels. If you’re interested in discussing your next project, whether stereo or stem mastering would work best for you, reach out at mixandmastermysong.com.
