Headroom (audio signal processing)

Last updated

In digital and analog audio, headroom refers to the amount by which the signal-handling capabilities of an audio system can exceed a designated nominal level. [1] Headroom can be thought of as a safety zone allowing transient audio peaks to exceed the nominal level without damaging the system or the audio signal, e.g., via clipping. Standards bodies differ in their recommendations for nominal level and headroom.

Contents

Digital audio

In digital audio, headroom is defined as the amount by which digital full scale (FS) exceeds the nominal level in decibels (dB). The European Broadcasting Union (EBU) specifies several nominal levels and resulting headroom for different applications.[ citation needed ]

ApplicationHeadroom
FM broadcasts−9 dBFS
Digital broadcasts and ordinary digital recordings−18 dBFS
Original master recordings−24 dBFS

Analog audio

In analog audio, headroom can mean low-level signal capabilities as well as the amount of extra power reserve available within the amplifiers that drive the loudspeakers.

Alignment level

Alignment level is an anchor point 9 dB below the nominal level,[ citation needed ] a reference level that exists throughout the system or broadcast chain, though it may imply different voltage levels at different points in the analog chain. Typically, nominal (not alignment) level is 0 dB, corresponding to an analog sine wave of voltage of 1.23  volts RMS (+4  dBu or 3.47 volts peak to peak). In the digital realm, alignment level is −18 dBFS.

Lindos10.svg

See also

References

  1. ↑ "Q. What exactly is 'headroom' and why is it important?". Sound on Sound. February 2010.

Further reading

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.