How to Remove Drum Bleed from a Vocal Track/Microphone

When you’re dealing with a vocal track, you ideally want the vocals and nothing else present on the track. In some recording circumstances, you cannot help but record alongside other instruments, which will introduce bleed into your vocal track. This is an especially big problem when it comes to drums which can bleed on both the high frequency and the higher frequencies thanks to the hi-hat.

But what can you do here and how can specifically remove drum bleed from your vocal track?

The best option is to prevent the bleed during recording with careful mic placement and strategic use of shielding or acoustic panels. If that’s not an option, then using gates, expanders, and filters in your DAW of choice can help you remove or at least greatly reduce drum bleed. 

That’s the quick answer but we’ll take a much closer look at all of your options. Let’s get started with how to prevent the bleed in the first place!

The Prevention Methods

The best way to deal with this bleeding problem is to catch it at the source, the time of recording!

Microphone

One of the first considerations to make here is the pattern of the microphone you wish to use for your singer. It will not completely drown out the bleeding, but every little bit helps.

The two main patterns are omnidirectional and cardioid. Omnidirectional microphones pick up audio in every direction from the microphone. This is great for when you wish to capture sound from every direction, but sadly this will grab a lot of drum bleed in your vocals.

The cardioid pattern is heart-shaped, positioned in such a way that the microphone mainly picks up audio from the front and sides but not from behind. This is great, as you can position the back of the microphone toward the drums to help prevent a little bit of bleed. The same technique can be used for any other instrument too and that makes cardioid mics a popular choice for acoustic guitar as well.

There are two more similar patterns following the normal cardioid, which are supercardioid and hypercardioid. They aim to narrow the width of sound the microphone can pick up, catching fewer stray sounds apart from what is directly in front. These can work as well but positioning can be a little more complicated.

Shielding and Acoustic Panels

Additional shielding around your vocal microphone and drum kit will be a great help in reducing the bleed. You can use a close proximity microphone shield that’s pointing in the direction of your drums to get the best effect of bleed reduction.

Microphone Shield

You can purchase a simple microphone shield to make this even easier and they’re usually pretty cheap. If you’re a little crafty, it’s also a very easy DIY project and this video will show how to do it in just a few minutes:

Drum Shield

If you have the space, a drum shield will shield the whole kit from other instruments in the room. It does not necessarily shield in all 360 directions, so this is best when pointed in the direction of your vocalist and their microphone to reduce bleed. Drum shields are a little price and it’s easy to pay around $500 for one of these. If you’re in a professional setting then investing in a proper drum shield will be worth it.

But if you’re building a home studio, then creating a DIY drum shield might make more sense. You have a lot of options here and you can usually pull this off for well under a hundred bucks. This is my favorite video on how to make this happen and while it’s not the most aesthetically pleasing drum shield it will get the job done:

Acoustic Panels

If you’re not already recording in a treated room, the last addition to your shield setup would be some acoustic panels placed in the area your microphone is facing. This is to stop the room reflections from the drums bouncing back into the microphone from the front angle, where these will be most prominent.

Selecting the right flooring can help here too but acoustic panels strategically placed on the walls will make the biggest impact just as you would if your goal was to reduce echo. If you’re dealing with a high ceiling, you can even consider placing some panels on the ceiling but that’s usually not needed outside of odd-shaped rooms.

You’ve probably noticed a theme at this point but you can buy acoustic panels but you can also go the DIY route. If you’re having trouble with snare bleed, then an acoustic panel is an especially good choice.

The Cure Methods

If you’ve already recorded your vocals and your audio track still has bleed, do not fear. There are still many ways to help suppress it and achieve much cleaner tracks on a DAW level.

Gates

The first line of defense in preventing bleed from your drums will be to apply a gate plugin to your vocal track.

Gates are simple to understand. They will allow sound to play once it breaks a defined threshold of dB. Here is an example of a simple Ableton Live gate:

There are a few important parameters here that you will need to play with in order to get it just right for your situation:

• Threshold – The dB at which your gate will open and allow audio to flow through.
• Floor – This determines the dB of attenuation of sound while the gate is closed.
• Attack – Length of time the gate takes to fully open once the audio breaks the threshold value.
• Release – Length of time the gate takes to fully close once the audio falls below the threshold value.

How do you use a gate?

A gate is very simple to set up with just a little bit of play, depending on your situation. Here’s a quick method for getting your gate in the ballpark area:

1. Start with the threshold at 0dB, with attack, release and floor at their lowest values.
2. Lower the threshold value until you can only hear the vocals you want whilst still excluding the drum bleed.
3. Raise your attack and release values to smooth out the opening and closing of the gate to your liking.

GGate is an example of a simple (and free) gate you can use on your vocals with only the most basic parameters needed. It is simple to use, with large knobs for easy viewing.

Expanders

Another method to gate better is to use an expander. They are the opposite of compressors; instead of squashing audio past a certain threshold, it expands the volume difference above and below the threshold.

Here is Ableton Live’s standard expander, containing very similar parameters to any compressor apart from the ratio and threshold:

• Threshold – This determines the dB from which the audio expands in either direction.
• Ratio – This determines the ratio by which the audio above the threshold is expanded. For example, at a ratio of 1:2, for every 1dB about the threshold, the output is multiplied by 2.

FabFilter Pro-G is a great expander/gate vst, which gives you tons of control over its effects on your vocals. It also comes with side-chaining capabilities to help with competing drum bleed frequencies. You can see a quick but detailed tutorial on how to use it here:

How do you use an expander?

When using an expander, you want your audio track to have a reasonably clear definition in volume of what you want to keep and what you want to expand against.

In this case, you want the threshold to sit below your vocal audio level but above the drum bleed, as this will increase the volume difference across the two, allowing you to gate the bleed easier.

Filtering

If the rumbles of the drum bleed are too close to your gate or expander threshold, they can trigger it every so often, creating a choppy effect on your vocal track. One great way of helping your gate/expander to function better is to attenuate the low frequencies that drum bleed might contain through the use of a filter.

Here is one of Ableton Live’s EQ’s:

This would be applied to your vocal track. Here, the lowest frequencies have been hi-passed up to around 100.0Hz. Drum bleed can sit largely in these lower frequencies, so using an EQ like this followed by a gate or expander will let the gate work even better. Of course, the frequency you are hi-passing will depend solely on your own situation, making sure not to modify the sound of your vocals too much.

Voxengo PrimeEQ is relatively easy to use and allows editing of up to 32 frequency bands. This will surely give you enough room to play with your vocal EQ, especially when dealing with high-frequency problems.

Drum bleed in the high frequencies

When it comes to drum parts, such as cymbals and other “vocal” frequency instruments entering the vocal track, then the methods above may not be viable at all or they may need to be altered.

One way to deal with the high frequencies in vocal tracks would be further filtering via an equalizer. You must figure out the biggest nuances in your cymbal sounds with a few sample hits and then attenuate those frequencies in your vocal track.

Drastic changes like this in EQ can greatly affect the sound of your vocals, so you will have to find that balance between vocal quality and reduction of cymbal bleed.

Conclusion

If you are stuck with a vocal track that has some drum bleed, it’s not the end of the world. If you have the chance, you should go back and record your vocals again with a better room treatment, as suggested in the samples above.

But otherwise, at the DAW stage, you still have a bunch of plugins, which are good at attenuating drum bleed in vocal tracks. They work best when the difference in dB from vocals and drum bleed are greater but can still improve the quality if they are a bit closer than you’re hoping.