So you've set up a home studio, have your interface and DAW all hooked up, and have managed to get a whole band over to make a record. Everyone's well rehearsed, and you've settled on one lofty goal: to make a record that preserves the performance. In other words, you want the tracks to maintain that "live" feel.
Since you aren't working in a professional space, you probably don't have the resources to stuff everyone into their own isolation booths. At the same time, you want your tracks isolated enough so that when it comes time for the mixing process, it’s not one giant glob of sound.
Bleed, a frequent troublemaker in recording, is when another instrument sneaks its way into the recording of a different instrument. Bleed is the enemy, and today we're going to share a few strategies you can employ to avoid bleed in your next session.
Use a Microphone in Cardioid
The first defense in preventing bleed revolves around microphone choice and placement. Every microphone has a pickup pattern that can be used to its advantage.
Cardioid — arguably the most utilized pattern — has a heart-shaped pickup pattern. As a result, it is designed to capture sound in front and to the sides of the microphone, but not behind it. This helps to reject unwanted sound from other instruments.
Check out some of the go-to options like the Shure SM57, Blue Baby Bottle, and the Shure SM7B.
Close-Mic the Source
The most efficient way to cut down on bleed is by close-mic’ing each source so that you get the most direct sound possible. When recording drums, this means trying to control your tone as much as possible by placing your kick drum mic right in the sound hole, the snare and tom mics right above the heads, and the overhead mics just above the kit.
Guitar and bass amps can have the microphone practically touching the grill cloth. Vocals are extremely important to mic closely as well, but not so close that the singer is overloading the microphone and distorting the signal.
Isolate the Cabinet
If you are alright foregoing a room tone on your amp, isolation boxes allow you to place your cabinet in a closed box while placing the amp head on top. This serves two purposes.
By placing microphones in the box, the cabinet can be recorded without having to worry about extraneous sound. Additionally, with the head on top of the box, settings can easily be adjusted without having to lift the cover on the box.
Run Guitar and Bass Direct
While committing to guitar and bass tones can help with decision-making in the mix process, it’s not always beneficial when tracking the whole band at once. There is some security in knowing that these instruments can be recorded directly into your DAW and committed to later.
You can accomplish this by using a DI box to circumvent amp settings and bleed from unwanted instruments. DI boxes are the only way to guarantee a 100% clean signal. Keep in mind that you can always re-amp the direct signal later on and customize the tone to your liking.
Some of the more popular DI boxes are the Radial JPC Direct Box, Countryman DT85, and the Avalon U5.
Separate your Vocals
In most cases, vocals are going to be the focus of the mix, so extra care needs to be taken in order to avoid bleed. The best practice here would be to place your singer as far away as possible from the loudest source.
Additionally, there are vocal-specific isolation panels that prove to be incredibly effective, such as the Talent VB1 Folding Portable Isolation Booth, Portable Microphone Studio Voice Booth Isolation Box, and SE Electronics Reflexion Filter Pro Vocal Booth.
Lastly, use a less-sensitive dynamic microphone like the Shure SM58, Shure SM7B, or Sennheiser 441 to further prevent unwanted extraneous sound.
Form Walls with Acoustic Panels
Another handy alternative to isolation booths are acoustic panels, otherwise known as gobos. They work to contain the sound of each instrument by forming makeshift walls. Combining multiple panels together will radically reduce the amount of bleed across instruments, but using one per instrument will work just fine.
The main component is acoustic foam, which does all of the absorbing. Most panels are two-sided so that unwanted sounds get absorbed as well.
The result of all this separation should hopefully be cleanly recorded tracks from each instrument. It’s also important to keep physics in perspective here. There are going to be reflections of sound that are likely to show up in some regard, and that’s okay. As long as it’s manageable the tracks will sound fine.
At the end of your session, the two questions you should be able to confidently answer "yes" to are whether you can mix your raw tracks and whether you truly captured the performance.