Stem Mixing/Submix

Hey there! I wanted to talk a bit about Stem Mixing; a method of mixing I use in practically every mix!

Stem Mixing (or sub-mixing) is the process of grouping audio tracks and setting the output to auxiliary tracks called ‘stems‘. Eg sending all the drum tracks to a ‘drums’ auxiliary, sending all the vocal tracks to a ‘vocals’ auxilary track, and so on! This enables greater control over levels of each instrument, being able to quickly and easily change the levels of, say, all the guitar tracks at once. Going even further, you can group different instruments together as aspects of the track, like Dave Pensado’s method:

  • All Drums
  • Music (Keyboards and Guitars)
  • All Vocals
  • Bass
  • All Effects
  • Hi-End (Cymbals)

In this video, Dave shows how stems can give you greater control over different aspects of the track. Changing the levels of these aspects can greatly affect the overall feel of the track. Here’s some examples:

  • Too much Bass can make the kick sound weaker, and give the track a more ‘urban‘ sound, whereas too little can leave it sounding empty.
  • Too little guitars can leave the voice and drums exposed, and make the track lose it’s power – sounding more ‘pop’ than ‘raw’, whereas too much can over-power the vocals and leave them sounding weak.
  • Too little high-end can leave the track sounding dull, whereas too much can over-power the brightness of other instruments and get too ‘washy‘.

It is important to realise, however, every genre suits a different mix of levels. Hip-hop and urban music suits more low end, rock suits more guitars, acoustic suits lots of vocals. Remember though! There is no right and wrong! Everything is subjective, and every mix is different!

Pro tip: When mixing, use other tracks in the same genre or style as the one you are working on as a reference. It is easy to get lost in your mix and lose perspective!

I find stem mixing makes the mixing process much easier, especially in the latter stages of mixing where you’re trying to polish everything off having got individual tracks sounding and interacting how you want them. It also helps in mixes with a large number of tracks, breaking the mix down into more manageable chunks!

Here’s an example of how I have broken a track down:

This mix had 38 audio tracks, which was almost un-workable in terms of mixing everything one by one. After getting each individual track sounding good (EQ, comp, etc) and interacting how I wanted them, I grouped them into categories to simplify the mix into a more manageable chunk. From there, I could add plug-ins to the stems and effect multiple tracks at once.

Every engineer would have done this differently! I chose to break things down this far and no more because I still wanted control over some details like the cello solo and double bass levels. Always organise a mix so you are comfortable with it, not just because some blog told you to do it some way! You are likely to get better results when you are happy!

Another use of stem mixing is in world of video games, as seen in the Amon Tobin ‘Infamous’ soundtrack. In this video, the audio is broken down into stem form and then organised into low, medium, and high intensity elements. These elements are brought in and faded out during game play depending on where the player is, and what he is doing at any specific time. During calmer periods, only low intensity elements would be present. As something is encountered by the player, medium intensity elements would be faded in. Finally, at high octane moments of gameplay, the intense elements would be brought in to heighten the players sense of involvement during intense periods. This adds excitement to fights and chases, while adding atmosphere and anticipation to less dynamic periods in the game.

This is a really cool way of thinking about stems. They don’t just need to group all the drums, or all the music; they can group any category of tracks together for ease of mixing!

David

Parallel Compression

Parallel compression (or the  New York compression trick) is a technique used to compress an audio track while avoiding squashing the attack/dynamics. This is a quick guide of how to use it to breathe some life into a drum kit!

Here’s the original un-compressed drum track:

Firstly, send the tracks you desire to be compressed to an auxiliary track via a bus (as shown below).

Then, add compression to the auxiliary track. This means the original un-compressed track plays alongside the compressed track. The original attack of the louder peaks are retained, but the quieter parts are subtly (or not so subtly, depending how the compression is applied) raised. Here’s the compression I used below, all buttons in so pretty extreme!

This technique can give a drum kit a sort of breathing sound, really livening up a dull sounding kit. Here’s the drum track blending the compressed signal with the original drum take:

If you can’t quite tell the difference, here it is changing between the two:

(I’ve been quite subtle with blending in the compressed track here, but this was done to taste. Experiment with different attack and release times as well as threshold and ratio to achieve the sound you want!)

Pro tip: As well as compressing an auxiliary track, you can try adding other effects such as distortion or saturation. Blend them in with the dry track to add character to instruments like bass guitar or synths!

David

Coming soon…

Thought I’d mention some things I’m going to be doing in the near future!

Recording

Recently I’ve been recording with Dawn Coulshed in the studio. We originally recorded two of her tracks ‘The Door’ and ‘Paper Butterflies’ a couple of weeks ago, but went back and re-recorded all the parts with some expensive microphones that made a huge difference as they really suited her voice and guitar (Neumann > AKG). Dawn also added some really nice harmonies to ‘Paper Butterflies’ that added to the dynamic of the track. I’ve done a quick mix of these but need to polish them off over the next few days before going back into the studio on Thursday. Look out for some uploads soon!

I’ve also been in talks with guitarist Stephen Maxwell about possibly recording a tune we played back in our 3rd year performance exams. Since this tune has a lot of improvisation and indefinite lengths of sections, we’ve decided it would be best to play it together first rather than in separate takes. We would probably play it through together until I got a drum take I liked (could take a while with my solo…) and overdub bass, guitar, and horns on top. We have yet to sit down and discuss our method of recording properly, but will probably do so on Tuesday when we’ll be having a rehearsal.

We have also discussed a more stripped back recording of ‘Oh Darling!’ by The Beatles featuring Emily KellyMaxwell and Emily played this track together for Emily’s vocal exam and would be a great track to record!

Playing

I am now part of the Tinderbox Orchestra which rehearses every Sunday in Summerhall. It is a contemporary youth orchestra which plays modern styles of music, writes original music and collaborates with top local bands and artists. We play classics such as ‘Fire‘ by Jimi Hendrix and ‘Paranoid Android‘ by Radiohead, as well as songs by Edinburgh artists such as Mike Kearney and North Atlantic Oscilation.

Elsewhere, I will be playing with Stephen Maxwell and Ally McLachlan in the Jazz Bar on December 13th for the Napier Songwriter Showcase to raise money towards the singers booking venues for their exams next year. Stay tuned for updates…

 

David