Where Mixing Ends & Mastering Begins

Mixing and mastering often get grouped together in the music production world. Many engineers who offer mixing services also offer mastering service. But is it the same as having a dedicated mastering engineer? It depends…

Most often, you’ll find that the biggest benefit of maintaining separation between your mixer and mastering engineer is that you get twice the amount of expertise on your project. Many mixers welcome the additional set of ears providing support and taking their work to new heights. I know several who refuse to master something they mixed – it’s not that they’re not capable; they’re just too invested in the mix to master their work objectively.

So it begs the question – where does mixing end and mastering begin? If someone has the capability to master a song, where do they draw the line and say they’re done? 

A Mixer’s Finishing Moves

When the process of mastering is left to someone else, mixers tend to be able to work more creatively. 

The reality is, when you know you’re going to be mixing and mastering a song, your process changes. You start making mix decisions anticipating the way those adjustments will impact your ability to master the song. You stop looking at the session as a mixer and start approaching things with a hybrid mentality – often one process or the other will suffer as a result.

By disconnecting the mix session from the mastering process, a mixer can focus on the things that matter to their primary objective: creating a great mix.

This means they can throw caution to the wind to an extent. Add that extra reverb or delay. Get your instrumentation balanced as you see fit and let the mastering engineer maximize those mix decisions later on.

The only thing you need to keep in mind as you work is leaving some headroom for mastering. If you’re slamming your output and clipping it, your mastering engineer won’t be able to do his or her job; just like you’d struggle if someone sent you a mix like that to master.

What Mastering Engineers Look For

A great mastering engineer is going to be able to take just about any source with sufficient headroom and maximize those results. Their role isn’t to create balance between instrumentation, but to get the final stereo mix sounding its best.

Often, this means using the same tools and techniques mixers are already using on individual tracks. EQs, compressors, transient shapers, and spatial wideners are all common in mastering setups – making entry into the space pretty easy for anyone already offering mixing services.

More importantly – it makes communication between mastering engineers and mixers easy. They’re generally speaking in the same terms and referencing the same principles, so feedback between the two groups is extremely transparent. While mastering engineers tend to use more multi-band processing than a mixer might, that’s rarely a communication barrier between them.

As a starting point when working with a new mastering engineer, leave them sufficient headroom to work with and any mix notes you think they might find useful as they maximize the impact of your work. Ask for feedback with each mix and learn what they like and dislike about your work.

Many mixers have preferred mastering engineers that they work with these days. It makes sense – once you find someone with a complimentary vision to your own, it can be a very symbiotic working relationship.

Where Mixing & Mastering Roles Overlap

The biggest overlap between a mixer’s session and a mastering engineer’s role is the mix bus. While used for monitoring, many mixers also use the mix bus as part of their sound – adding compression and other effects to shape their signature style.

There’s absolutely nothing wrong with that so long as your sessions retain headroom and dynamic range. The more you’re able to keep, the more your mastering engineer has to work with.

For sessions that won’t be mastered by someone else, the mix bus is also a great place to start experimenting with some light mastering. There’s a growing trend of home studios with a mastering chain – a compressor, limiter, and/or other mix bus processors designed to mimic the results of a professional mastering rig.

While these mastering chains don’t replace the need of a highly skilled mastering engineer with a fine-tuned listening environment, the results speak for themselves when done just right. Don’t over compress your sessions and keep your transients dynamic and punchy and you’ve got a recipe for success.

A Deep Challenge for Mixers

When stereo mixes get handed off for mastering, you’d be surprised how much low-end clean up is needed. Often, mixers don’t even realize how prevalent the problem is. Whether due to a poor listening environment, equipment that can’t reproduce those frequencies accurately, or even just ignorance - bass can be an overwhelming issue that’s killing your dynamics. 

If you want to proactively clean-up that bass, you’ll not only give the mastering engineer more room to work with, but you’ll also find your mixes start sounding tighter and more professional almost instantly.

Check out our eBook, Basscrusher: An Unholy Guide To Bass Tone, for more information on the topic.