Adobe 22012057DM User Guide - Page 83

Digital audio glossary, Common audio terms, A, B, C

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79 Chapter 11: Digital audio glossary The glossary is your guide to unfamiliar terms in common audio workflows and multiple Adobe Soundbooth CS3 features. If you don't find a term here, search for it in Help to find a feature-specific definition. Common audio terms A ADC (analog-to-digital converter) The hardware that converts an analog audio or video signal into a digital signal that you can process with a computer. aliasing Noise that occurs when a high frequency sound exceeds the Nyquist frequency for a given sample rate. (See "Nyquist frequency" on page 82.) Most analog-to-digital converters prevent aliasing by filtering out sounds above the Nyquist frequency. amplitude Amplitude represents the volume of an audio signal. A waveform's amplitude is measured by its distance from the center line, which represents an amplitude of 0. There are different standards for measuring amplitude, but the decibel (dB) is the most common. (See "decibel (dB)" on page 80.) analog recording Traditional audio recording with devices such as magnetic tape machines and vinyl records. Analog audio recording consists of a continuous curve, as opposed to digital recording, which consists of discrete samples. ASIO (Audio Stream In/Out) A standard for low-latency drivers, created by Steinberg Media Technologies. attack The first part of the sound that you hear. Some sounds (like pianos and drums) have a very fast attack; the loudest portion of the sound occurs very quickly. A sound with a slow attack rate (such as a soft string section) slowly increases in volume. attenuate To reduce volume or signal level. B band pass filter A filter that allows some audio frequencies to pass through unchanged. beats per minute (bpm) Musical tempo, which is defined by the number of beats that occur every 60 seconds. bit depth The number of bits used to represent audio amplitude. For example, 8-bit resolution provides 256 possible amplitude levels and a 48-dB dynamic range; 16-bit resolution provides 65,536 levels and a 96-dB range. Soundbooth supports up to 32-bit resolution with 4,294,967,296 possible levels. For the best audio quality, remain at 32-bit resolution while transforming audio in Soundbooth, and then convert to a lower bit depth for output. C clipping In digital audio, distortion that occurs when the amplitude of a signal exceeds the maximum level for the current bit depth (for example, 256 in 8-bit audio). Visually, clipped audio produces broad flat areas at the top of a waveform. If you experience clipping, lower the recording input or the source output levels.

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79
Chapter 11: Digital audio glossary
The glossary is your guide to unfamiliar terms in common audio workflows and multiple Adobe Soundbooth CS3
features. If you don’t find a term here, search for it in Help to find a feature-specific definition.
Common audio terms
A
ADC
(analog-to-digital converter) The hardware that converts an analog audio or video signal into a digital signal
that you can process with a computer.
aliasing
Noise that occurs when a high frequency sound exceeds the Nyquist frequency for a given sample rate. (See
“Nyquist frequency” on page 82.) Most analog-to-digital converters prevent aliasing by filtering out sounds above
the Nyquist frequency.
amplitude
Amplitude represents the volume of an audio signal. A waveform’s amplitude is measured by its distance
from the center line, which represents an amplitude of 0. There are different standards for measuring amplitude, but
the decibel (dB) is the most common. (See “decibel (dB)” on page 80.)
analog recording
Traditional audio recording with devices such as magnetic tape machines and vinyl records.
Analog audio recording consists of a continuous curve, as opposed to digital recording, which consists of discrete
samples.
ASIO
(Audio Stream In/Out) A standard for low-latency drivers, created by Steinberg Media Technologies.
attack
The first part of the sound that you hear. Some sounds (like pianos and drums) have a very fast attack; the
loudest portion of the sound occurs very quickly. A sound with a slow attack rate (such as a soft string section) slowly
increases in volume.
attenuate
To reduce volume or signal level.
B
band pass filter
A filter that allows some audio frequencies to pass through unchanged.
beats per minute (bpm)
Musical tempo, which is defined by the number of beats that occur every 60 seconds.
bit depth
The number of bits used to represent audio amplitude. For example, 8-bit resolution provides 256 possible
amplitude levels and a 48-dB dynamic range; 16-bit resolution provides 65,536 levels and a 96-dB range. Soundbooth
supports up to 32-bit resolution with 4,294,967,296 possible levels. For the best audio quality, remain at 32-bit
resolution while transforming audio in Soundbooth, and then convert to a lower bit depth for output.
C
clipping
In digital audio, distortion that occurs when the amplitude of a signal exceeds the maximum level for the
current bit depth (for example, 256 in 8-bit audio). Visually, clipped audio produces broad flat areas at the top of a
waveform. If you experience clipping, lower the recording input or the source output levels.