It’s a fact of recording studio life – bleed happens.
‘Bleed’ is the residual sound picked up by microphones placed around the studio to capture multiple instruments. For example, it happens when a microphone placed next to an acoustic guitar also records sounds from vocalists and other instruments being played close by. Many producers and engineers believe bleed is something to be minimised and removed as much as possible. With pesky bleed in the way, it can be much harder to perform magic tricks like overdubbing and editing later on. Common strategies to reduce bleed include putting up sound barriers up between instruments, positioning microphones very close to the instrument or simply recording instrument tracks one at a time.
These strategies can have some unintentional consequences though. Putting up sound barriers can kill the vibe of a band playing together. Positioning microphones too close to instruments can also produce an exaggerated and unnatural sound on playback. And recording your instruments one at a time? Sure, you’ll have no problems with bleed, but if you’re recording a bunch of great musicians you might be killing the vibe unnecessarily. They rehearse and perform together, what do you think will happen when you make them play their parts individually one at a time? If you’re recording musicians who aren’t that great, you probably need to record them separately anyway.
Don’t worry about bleed. Good musicians who know what they’re doing don’t need magic tricks to fix up mistakes. Just play good music and the rest will take of itself.