So you’ve been asking yourself, should you compress the master bus track when mixing.
The are who rather leave this type of compression to the mastering engineer so they would never put compression on their master bus.
While other mix engineers will not go without the sound achieve by using stereo bus compression.
Coming up in the article, we outline what is master bus compression, answer the question ‘should you compress the master track’ and list three best bus compression.
What is master bus compression
Simply put, master bus compression is using a compressor on the stereo output track to achieve a more cohesive mix.
Stereo bus compression, mix bus compression, 2-mix compression or master bus compression all mean the same thing.
When used effectively, master bus compression can improve the mix, but if not used correctly, it can destroy the mix.
Consequently, there is a continuous debate on when or not you should use compression os the master track, which have created a misconception on how and why stereo bus compression is used.
Should you compress the master bus track
Mix bus compression is an excellent tool you can use to create a cohesive mix.
It is a technique every young engineer can learn that will help enhance their mix future.
But used incorrectly, stereo bus compression can ruin a mix or cause you to make poor balance decisions.
Many professional mix engineers prefer to control the mix dynamic internally and leave the master bus processing to the mastering engineer.
The best way to know if mix bus compression suit your mixing style is to mix the same song twice. One with compression on the master bus and the other without any compression.
This is an easy way to hear how master bus compression affects the overall mix.
When to apply mix bus compression
There are two ways to adding the compressor to the master bus. You can add it at the beginning of the mix or the end of the mix.
Both approaches affect the mix in different ways. Adding the compressor at the end of the mix changes the dynamic and tone of the original mix.
You can lose the balance of the mix you have been working on if the compression setting is too aggressive.
Many professional engineers suggest adding the compressor at the beginning and shape the mix into it.
This way, you can hear how the compressor shapes the mix as you are making any adjustment.
Mix bus compressors
You may decide that you want to compress the master track, but which compressor should you use?
There is a range of 2-mix compressors, some colourful and aggressive and others that are gentle and transparent.
Your choice of mix bus compressor depends on the sound you are trying to achieve.
Below is a list of the best and most popular mix bus compressor available to you and how they affect the mix.
Fairchild 670 Emulators: The original Fairchild compress/limiter is known for its ability to increase loudness with very little distortion.
In addition, the Fairchild compression is also renowned for its explosive drum and heavy bass sounds.
Wave PuigChild 670 and UAD Fairchild Tube Limiter Collection are the two most popular plugin emulation of the Fairchild 670.
SSL G Series Bus Compressor: You may have already heard all the nice things about the SSL bus compressor from both professional and non-professional mix engineers.
The SSL bus compressor has a reputation for its big punchy sound and the unique ability to glue the mix together.
Thus, it is a go-to bus compressor for many mix engineers for transparency and glue.
Two reputable SSL G series bus compressor plugin emulations are Universal Audio SSL 4000 G Bus Compressor and Waves SSL G-Master Buss Compressor.
API 2500 Bus Compressor: Known for its versatility and its ability to adjust the sonic qualities to achieve a wide range of sounds from punchy to smooth.
The patented THRUST circuit produces punchy lows and the selectable ‘old’ or ‘new” compression also adjust the compressor’s tone.
Both Universal Audio and Waves has an API 2500 Bus Compression plugin.
Master bus compression settings
Setting up the master bus compressor is much like setting up a compressor on an individual track or instrument, but with a few exceptions.
Typically, mix bus compression uses low ratio settings, usually 2:1 and below.
And the threshold level is set to achieve a small amount of gain reduction – a maximum of 3 dB of gain reduction.
The attack and release work in the same way as it does on every compressor.
A fast attack will suppress transients, whilst a slow attack time leaves them untouched.
Setting a very fast attach time on a dynamic mix with lots of transients will produce a flat mix with weak drums.
The release, on the other hand, is not as easy to comprehend, but it is the key to getting the mix bus compression to work for the mix.
Master bus compression relies on the tempo and the groove of the song.
The compress must pulse in time with the mix, and this achieves using the release setting.
An incorrect release setting can choke the life out of the mix or cause an unpleasantly pumping effect that can compromise the vibe of the song.
Upbeat songs with a faster tempo would require a fast release time. Slow tempo song like a ballad would need a slower release setting.
The best way to find a suitable release time is to monitor to gain reduction VU meter. The needle should move in time with the song you are mixing.
So for every time the instrument that is driving the mix trigger gain reduction, the meter needle should return to unity gain before the next trigger.
If however, you can’t find a specific instrument that’s driving the mix, it better to use auto release.
Whether are not you should you compress the master bus is irrelevant, it’s how you use it that’s important.
Audio compression on the master bus can have a drastic effect on the mix. Therefore subtle compression is better than aggressive compression.
Adding a compressor to the master bus after the final mix can upset the balance you’ve already created. It’s best to mix into the compressor.
The type of compressor you use also impact the final mix, as each compressor have it own unique tone.
Spend a little time with your favourite compressors so you can learn how they sound..