Bleeding, Bleed, or Bleed-Through
A slang term which refers to the ambient sounds that a microphone aimed at instrument A picks up from other instruments or singers in the same room. In some cases, “bleeding” is considered undesirable, if unwanted sounds from other instruments are picked up by a microphone. For example, if a guitar player plays an amazing solo during a recording, it may end up being unusable if mistakes by the drummer—20 feet away—are bleeding through into the mic in front of the guitar amp. To prevent “bleeding”, studios use isolation booths and cloth-covered room dividers.