A mix bus is a channel where your instrument channels are sent. When you apply an effect to the bus track, it affects all channels that are routed to it.
A real bus is the greatest metaphor for a mix bus.
Assume that every channel in your DAW is a person. The mix bus channel, meanwhile, is a real bus.
You may direct specific individuals (channels) to board the bus. The passengers (channels) will then follow the bus in any direction.
If you send the bus down the reverb road, for example, reverb will be added to all of the bus’s channels.
A mix bus duplicates a channel’s signal, applies the effect, and then inserts the signal back into the mix.
Mix Bus vs. Master Bus
To be clear, a mix bus is not the same as a master bus (AKA the master track).
If a bus track represents a bus carrying children, the master bus represents a ferry that transports such buses and schoolchildren.
The master bus feeds all of the channels in your DAW.
You should never add effects to your master bus as a general rule. When you bounce the track for mastering, this will mess it up. Just stay away from the master bus.
Why Should Tracks Be Routed To A Mix Bus?
Why go to the effort of making a mix bus track in the first place?
Because a bus track duplicates the transmission, the original signal is unaffected. As a result, both the original and the copy are under your control.
Let’s have a look at this in practice…
You want to give your voice some reverb. It would be OK if you applied the reverb effect straight on the voice recording.
However, there is an issue with this.
It’s tough to adjust the quantity of reverb (i.e. the wet vs. dry signal). You must modify the plugin once it has been opened.
When you have several voice files with the same reverb effect, this becomes a major issue. Change the reverb settings for all of them, or for each of them individually.
You may alter the setting on the bus track, which will change the effect on all of the tracks, rather than opening the effect on each individual track. Alternatively, using the bus track, you may easily change the amount of reverb on each track.
Using bus tracks will simplify your life and improve your mixes significantly.
What Is A Mix Bus And How Do I Set One Up?
Compression, reverb, delay, and EQ are the most typical effects used with a mix bus.
Here are the procedures to make a mix bus for each of these:
- Make a new song.
- Title it “[effect] bus”
- Choose “send” from each channel or add a “receive” of each channel from the bus track to route the appropriate channels to this bus track.
- Adjust the settings from the bus track
Here are some ideas for combining those four effects.
Compression on the mix bus makes your songs seem more cohesive. It maintains a constant volume level throughout and makes everything sound more lively.
Mix bus compression, like everything else in mixing, works best when it’s unobtrusive. Try the following options:
- Use a ratio around 2:1 to lightly compress the tracks
- Start with a slow attack (try 30 ms) and a fast release (keep it under 50 ms)
- Apply no more than 2 dB of compression.
This works best when the bus compressor is applied before you begin mixing. If you mix your track and then add a bus compressor, the dynamics you worked so hard to get may be totally altered.
Reverb & Delay
A bus reverb and/or delay may be used to apply a specific reverb or delay to several tracks (such as your voice). Separate bus tracks should be used for these effects. You’ll have greater control, and adjusting the parameters for several songs at once will be simpler.
However, there is another way to add space and breadth to your mix.
A bussing technique that a buddy of mine taught me has drastically enhanced my mixes.
Here’s how you go about it:
- Make two new tracks: a “Delay Bus” and a “Reverb Bus.”
- Apply your preferred reverb and delay effects to the reverb and delay buses, respectively.
- Except for the bass, drums, and percussion, route every track in your DAW to one of these bus tracks.
- Reduce the bus tracks’ gain settings to the point where the impacts are practically undetectable.
This may give your music a sense of depth and spaciousness. But remember to keep it quiet.
To be clear, the primary EQing must be done on each individual track. Different frequencies may need to be reduced or boosted for each instrument.
Mix bus EQing is useful for making minor adjustments to a collection of songs.
You may bus a bunch of voice tracks to an EQ track and reduce or enhance them if they’re overwhelming. Use a mix bus EQ if your cymbals require a little shimmer.
Stick to tiny motions, like with everything else in mixing, particularly on a mix bus. A little shift in the frequency spectrum may have a significant impact.
As a result, employ broader bands and smaller slices (no more than 2 or 3 dB). This is not a surgery, but rather a way to sculpt the tone. If necessary, do surgery on the individual tracks.
Mistakes to Avoid When Using A Mix Bus
Mixing is a delicate skill, and adding bus tracks makes it much more so. As a result, it’s quite simple to make errors. That’s why I’m going to go through some of the most frequent mix bus blunders.
The First Mistake: Spending Money on Plugins
Using a mix bus does not need the purchase of any plugins. You can mix a track to industry standards using stock plugins.
I’m not saying you shouldn’t upgrade, but knowing how to use a mix bus is much more essential.
For the time being, you may use a stock plugin.
The second Mistake: Making Major Changes
It bears repeating: mixing is all about little tweaks.
When you’re making changes to several tracks at once, you’ll notice the difference much more.
Here are some pointers on how to make tiny movements:
- Compression: use a 2:1 ratio
- Compression: shoot for 1-2 dB of gain reduction
- Compression: use a slow attack time (start between 30-50 ms)
- Compression: use a fast-but-not-too-fast release time (keep it under 50 ms)
- EQ: use wide bands
- EQ: make small cuts and boosts (no more than 2-3 dB)
- Reverb & Delay: keep the levels lower than you think they should be so they don’t overpower the mix
When in doubt, go for the safe option.
The third Mistake: Finishing With A Compressor
I discussed it briefly before, but utilizing a mix bus compressor only works if you’re mixing with it already on.
Compression may alter a track’s dynamics and tone, thus using it after you’ve already mixed it might destroy it.
Install a mix bus compressor before you begin mixing.
I hope you can see how beneficial a combination bus may be. It’s more practical, and it may make your mixes sound more professional.
Just keep in mind that little changes may make a huge impact.