Operation Manual

ADOBE AUDITION 3.0
User Guide
277
normalize To adjust the highest peak of a waveform so it nearly reaches the digital maximum, 0 dBFS, thereby
raising or lowering all other peaks accordingly. Typically, audio is normalized to 100% to achieve maximum volume,
but Adobe Audition lets you normalize to any percentage.
Nyquist frequency A frequency equal to half the current sample rate, which determines the highest reproducible
audio frequency for that rate. For example, audio CDs use a sample rate of 44,100 Hz because the resulting Nyquist
frequency is 22,050 Hz—just above the limit of human hearing, 20,000 Hz. For the best audio quality, record and edit
at higher sample rates and then convert down if needed.
O
offline processing Intensive effects processing that requires dedicated computer power, briefly preventing you from
editing audio. (Compare with “real time” on page 277.)
order A value that determines the slope of an audio filter. First-order filters attenuate an additional 6 dB per octave,
second-order filters attenuate 12 dB, third-order filters 18 dB, and so on.
P
PCM (pulse code modulation) PCM is the standard method used to digitally encode audio and is the basic, uncom-
pressed data format used in file formats such as WAV and AIFF.
phase The position of a sound wave relative to other sound waves. As a sound wave travels through the air, it
compresses and expands air molecules in peaks and troughs, much like an ocean wave. In the waveform display,
peaks appear above the center line, troughs appear below. If two channels of a stereo waveform are exactly opposite
in phase, they will cancel each other out. More common, however, are slightly out-of-phase waves, which have
misaligned peaks and troughs, resulting in duller sound. (See also “Waveform measurements” on page 8.)
pink noise Noise with a spectral frequency of 1/f, producing the most natural-sounding generated noise. By equal-
izing pink noise, you can simulate rainfall, waterfalls, wind, a rushing river, and other natural sounds. On the audio
spectrum, pink noise falls exactly between brown and white noise.
plug-in A software component that you can add to another piece of software to increase its functionality. Adobe
Audition supports third-party VST and DirectX audio plug-ins, which seamlessly integrate into Adobe Audition’s
interface.
punch in A recording method used to insert a new recording into a specific region of an existing waveform, usually
to replace an undesirable section. Adobe Audition supports punch-in recording in Multitrack View and allows for
multiple takes; you can repeatedly record over the original material and later choose the best performance.
Q
quantization A process that occurs when an analog waveform is converted to digital data and becomes a series of
samples. Quantization noise is introduced as some samples are shifted to quantization levels allowed by the current
bit depth. This noise is highest at low bit depths, where it can particularly affect low amplitude sounds.
R
RCA cable Sometimescalledaphonocable,RCAcableshaveRCAplugsorjacksateitherendandarenormallyused
to connect stereo system components, such as receivers, CD players, and cassette decks.
real time In computer-based audio, real time refers to functions that immediately respond to user input. Note,
however, that system speed ultimately determines processing time. Adobe Audition provides real-time mixing and
effects in Multitrack View, and real-time previews in Edit View. (Compare with “offline processing” on page 277.)