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headroom

  1. Headrooms in music production

    In music production and concerts, the volume levels that occur can only be estimated in advance. The headroom is the difference in level between the reference level and the working level. It is selected as large as possible for music productions, live concerts and sound reinforcement tasks so that any peak levels that occur do not exceed the headroom range and thus lead to distortion. Affected by the headroom are all devices in the acoustic chain such as amplifiers, mixers and recorders. Headroom is the headroom between the possible maximum level, which is defined as 0 dBFS (Decibel Full Scale) for full scale, and the nominal level.
    Relationship between headroom, dynamic range, footroom and signal-to-noise ratio

    Relationship between headroom, dynamic range, footroom and signal-to-noise ratio

    The headroom is always directly related to the level meter used. In Germany, DIN 45406 applies, according to which 100% DIN corresponds to -9 dBFS, which is equivalent to +6 dBu (Decibel Unloaded). The alignment sine level is 35 % according to DIN and corresponds to -18 dBFS or -3 dBu (Decibel Unloaded). In general, there are differences in headroom between analog and digital signals, as well as in the device technology. Analog technology is less sensitive to overloads than digital technology, although tube technology still has certain advantages over transistor technology, since distortion in tube technology is much softer and not as abrupt as in transistor technology.
    Dynamic range of various media

    Dynamic range of various media

    In practice, professional analogaudio mixers and other analog audio components operate at a level of about 20 dBu. If the European studio level of 6 dBu is taken as a basis, then the headroom is 14 dB, which provides a sufficiently large working range. The headroom should always be specified in conjunction with the headroom meter used, for example with a VU meter or a DIN headroom meter. The situation is different with digital audio components that do not know any headroom, but only the maximum audio level of 0 dBFS. These devices have the highest level at 0 dBFS. The level can be set arbitrarily and the level range above this can be called headroom.
  2. Headrooms in video technology

    In contrast to audio technology, headroom in digital video technology is the signal range that lies above 100% white, the ultra white. This white areais suppressed when the signals are transmitted. Originally, this area was used to intercept positive signal peaks so that no overshoot and possibly sign reversal of the video signal could occur. A digital video signal can thus use an additional 9% headroom without overflowing into the black area. The total dynamic range is thus 109%. This level control range can be used for level control of SDI signals. On modern DVDs and in the corresponding playback devices, these values are reproduced and thus increase the available signal dynamics.
Informations:
Englisch: headroom
Updated at: 04.11.2013
#Words: 449
Links: level, sound, lead, distortion, dB full scala (acoustics) (dBFS)
Translations: DE
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