headroom

Definitions

General English

  • noun the amount of space needed to be able to sit or walk upright

Cars & Driving

  • noun the distance between the top of a passenger’s head and the inside of the car roof

Electronics

  • A measure of the difference between the typical operating level of a device, piece of equipment, or system, and the maximum operating level before clipping or overload occurs. For example, an audio amplifier which nominally operates at +5 dB, and which clips at +25 dB, has 20 dB of headroom. This enables the amplifier to adequately handle peaks. In the case of tape recording, headroom refers to the level above the 0 point on its VU meter at which tape overload occurs. For example, if there in no tape overload until +6 dB, then there are 6 dB of headroom. Also spelled head room.

Media Studies

  • noun the amount of space in a photographic image between the top of the subject’s head and the top of the frame
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