Clipping

Technology / Home Audio / Clipping: A signal that results from an amplifier that is either overloaded or underpowered relative to the signal Amplitude it being asked to generate. A clipped waveform is one in which the gently rounded peaks and valleys of the AC audio wave are instead sliced off or clipped, to yield what looks a lot like a square or alternating DC wave. When DC is applied to a speaker, the voice coil has no means of propelling itself relative to a constant magnetic field. Instead, it can only convert the incoming current to heat, and ultimately burns up. The effect of alternating DC on speakers is remarkable, irritating, painful, and short. If you are able to hear evident Distortion at high volume levels, or smell smoke, reduce the volume. It may already be too late for your speakers, but at least you may be able to save the amplifier.
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Headroom

Technology / Home Audio / Headroom: A term related to the dynamic range of amplifiers, used to express in db, the level between the typical operating level and the maximum output level (onset of clipping). For example, a nominal +5 dbu MORE

Limiter

Technology / Home Audio / Limiter: An electronic compressor with a fixed ratio of 10:1 or greater. The dynamic action effectively prevents the audio signal from becoming any larger than the threshold setting. For example, if the thresh MORE

Distortion

Technology / Home Audio / Distortion: Any departure from a true and accurate reproduction of the original waveform. It can include Noise, Clipping Distortion, Harmonic, and Intermodulation Distortion. These last two forms are fairly commo MORE