Getting More Surgically With Stem Mastering

Stem mastering is different from 2 track stereo mastering. Stem mastering uses a number of grouped instruments such as drums, keyboards, bass, guitars and vocals. For electronic styles typical stems might be drums, bass, sub bass, lead synth 1, lead synth 2, effects sweeps etc. 

This allows the mastering engineer additional scope to discreetly enhance and optimize any specific set of instruments within a mix. It also affords enhancement based on the summing of the stems. Additionally, standard stereo mastering processes are included. 

Stem mastering can produce improved sonic results and increased depth and dimension to your master.It is worth clarifying that stem mastering is not mixing. Mixing uses heavy fader and send automation, effects, tuning etc. Stem mastering tends to only use occasional automation, but does allow the mastering engineer to target the use of eq, dynamic adjustment and other forms of processing to the individual stems often producing an improved master. 

When is stem mastering worth considering?

Stem mastering is worth considering if you feel there are some specific issues which could be improved upon by a fresh set of ears in a highly linear monitoring environment. If your mix is lacking separation, width and depth, stem mastering can help you achieve this. It can be used to target specific elements within a mix. 

Stem mastering is not the same as mixing. Mixing balances individual multi track recordings and involves many man hours and often heavy use of automation, equalization, dynamic control and effects processing.

Stem mastering tends not to use lots and lots of automation, occasional tweaks are more common. Stem mastering uses groups of instrumentation and allows additional sonic tweaks and targeted adjustment in addition to global stereo processing. Stem mastering allows additional and specific enhancement to instruments such as width, depth, warmth, punch, gluing, summing improvements, eq improvements, adding “air” and reduction of harshness.

So how do I prepare tracks for stem mastering?

Firstly, it is important that your stems “sum or re-combine” to sound identical to your mix down. Please supply full bandwidth 24/32 bit stereo files of identical length/duration. Export your stems from exactly the same time code position in your digital audio workstation time line so they will synchronize in our digital audio workstation. 

This will invariably involve setting left and right locators when you bounce/export your files. When preparing files consider that ideal stems should combine/sum in your digital audio workstation and sound virtually identical to the stereo mix down when combined and played together. 

If you are including your mix bus limiter processing when bouncing each stem, the limiter will be reacting in a different way than when playing the full mix. This means that the resulting combination of stems will NOT sound the same as your mix! We recommend one of the following solutions:

If your limiter has a side chain input, you can feed this with a full version of your mix whilst bouncing stems. This way the limiter will be forced to react as if it is receiving the full mix and your stems should then combine to sound the same as the mix. 

We recommend that you always listen to the resulting combined stems to make sure they sound identical to your mix. 

If your limiter does not feature a side chain input, we recommend that you bypass the limiter whilst bouncing stems. Please then include  a stereo mix with the limiter on in addition to your unlimited stem exports, so we can hear what you have been hearing. It would also be helpful to let us know which limiter you were using along with the settings used. 

If you are at all unsure on anything relating to stem preparation, please feel free to give us a call and we can guide you through the process. If you have any reference tracks that you aspire to (i.e. commercially released tracks) by all means send them along as a guide. This is really helpful to us to understand your tonal and perceived volume aspirations.

Any notes about sonic issues that have been of concern during the mix would also be helpful. Pointers like “bass line sounds muddy”, “cannot get bass line working with kick”, “drums require more punch” etc could be useful. Also please confirm the aspects of the mix you are happy with so we can avoid changing things you like already.