Backing vocals are important, yet so many people neglect them. When they are mixed well, they play a supportive role that enhances the whole track—but when they're mixed badly they can be distracting and poorly placed in the mix.
Efficiency is also important when mixing backing vocals. You don't need to spend a lot of time on them.; you just need a system that allows you to mix the backing vocals fast and effectively.
In this tutorial, I'll give a step-by-step breakdown of my process for mixing backing vocals.
When to Mix the Backing Vocals
Before you mix the backing vocals, you need to mix the lead vocal. In general, it's best to mix the lead vocals after the rest of the instrumentation. Many mix engineers have observed that the thing they mix last is often the loudest. By mixing the lead vocal towards the end, you subconsciously make it louder.
Mixing the lead vocal last—but before the backing vocals—also allows you to consider the EQ adjustments in the context of the entire mix. If you mixed the lead vocals first, you would have no idea of their context of the mix and where to cut or boost frequencies.
Once you've finished mixing the lead vocal, you can move onto the backing vocals. Now that you know which frequencies are being boosted in the lead vocal, you can take this into account when EQ'ing the backing vocals.
I find myself using the same system every time I mix backing vocals. By implementing this system, you'll be able to mix faster and more efficiently—but it will also guide you towards making better mixing decisions. In the end, this means better mixes in less time.
Step 1. Volume Balancing
Far too many skip over this vital step. The majority of your mix comes from the volume relationship between the parts. You need to spend plenty of time setting the level of each backing vocal part.
Start by creating a group buss for all of the backing vocals.
This allows you to adjust the volume of every vocal at the same time. It also allows you to add processing—such as EQ and compression—to all of the backing vocals at once.
Now solo all of the backing vocals and spend several minutes setting the volume balance between them. Every part should be audible, but it is also important to maintain an equal balance between the parts.
Next, turn off solo and listen to the backing vocals in the context of the mix. Adjust the fader on the group buss until the backing vocals sit nicely underneath the lead vocal. They shouldn't be anywhere near as loud as the lead vocal part, but should still be clearly audible.
Step 2. Copy Over the Lead Vocal Plugin Chain
This is a great trick for saving time when mixing. There's no need to spend time processing each individual channel. Nor is there any need to start from scratch. Instead, copy every plugin from the lead vocal channel onto the backing vocals group buss.
Step 3 - Adjust the Compressor
The compressor will already be set up for vocals, but I can adjust it slightly to ensure the compressor is suited to backing vocals.
Start by adjusting the threshold until around 5dB of gain reduction is being applied—check the meter on your compressor.
One of your main goals with backing vocals is to stop them interfering with the lead vocal. Using a faster attack time helps to achieve this.
By clamping down on the transients of the vocals with a fast attack time, you can make them sit better in the mix and stop them from poking out as much as the lead vocal.
The next step, then, is to speed up the attack time—below 5ms usually works best.
A lot of backing vocal parts are more sustained than a lead vocal. For this reason, you'll also need a slower release time—otherwise there might be noticeable pumping from the compressor. Slow down the release time—above 100ms is a good guideline—and then move onto EQ.
Step 4. Adjust the EQ
The fastest and easiest way to apply equalization to backing vocals is to simple reverse the EQ of the lead vocal. As you've already copied the EQ across from the lead vocal channel, this is as easy as going through and reversing every adjustment.
For example, if the lead vocal was boosted at 1kHz, cut the backing vocals at 1kHz. If the lead vocal was cut at 4kHz, boost the backing vocals at 4kHz.
By cutting you are creating space for the lead vocal part in the mix. By boosting, you are giving the backing vocals their own space in the mix that won't interfere with the lead vocal. Again, you should be applying this EQ on the group buss, not to each individual vocal channel.
If you find that the boosted frequencies don't suit the tone of the backing vocals, feel free to adjust the frequency. Just make sure you cut the backing vocals where the lead vocal part was boosted—this is the most important step here.
You can also adjust the high-shelf. Use a boost to add more top end to the mix, or cut the highs to put the backing vocals further back in the mix and create more depth.
Finally, remove a lot of the low end from the backing vocals with a high-pass filter around 100-200Hz. You might also need to apply a subtle cut somewhere between 200-500Hz to remove some mud. Just make sure you do this in the context of the mix—avoid applying EQ in solo.
Step 5. Apply Reverb
If you already have a reverb set up on an aux/effect buss, add a send from the backing vocal buss to the reverb channel. You can be more liberal with reverb on the backing vocals, as this will also help to put them further back in the mix.
If you don't have a reverb channel set up, you can apply reverb directly to the backing vocal group buss. Use a small room if the mix is relatively dry, or use a long reverb as a creative effect.
Step 6. (Optional) Apply Sidechain Compression
If the backing vocals are still getting in the way of the lead vocal, add a compressor to the backing vocal group buss and sidechain it to the vocals.
Adjust the settings until 2-3dB of gain reduction is applied whenever the lead vocal part comes in.
Step 7. (Optional) Use a Gate to Clean Up the Timing
Backing vocals should be as consistent as possible. Every part should start and end at exactly the same time. However, this often isn't the case. The different vocalists or takes end at slightly different times. This can sound messy and unprofessional.
To fix this, add a gate or downwards expander to the backing vocals group buss. Adjust the threshold so that the gate clamps down when one or two of the parts finish. Now set the hold time to 0ms and use a slow release around 200ms.
This cuts off the end of parts that trail on a bit too long.
With backing vocals, efficiency is the name of the game. You don't need to spend too long on them
By copying the plugin chain from the lead vocal you can save a lot of time. After that, just make sure the vocals sit well in the mix without interfering with the lead part.