Specifications
EAW Smaart 6 Operation Manual Concepts, Glossary, and Bibliography
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FFT Time Constant: The amount of time it takes to collect all the samples required
for a single FFT frame of a given size at a given sampling rate. The time constant of an
FFT, also called the time window, can be calculated by dividing the FFT size by the
sampling rate. For example, a 4k FFT sampled at 44.1k samples/second has a time
window of 0.09 seconds.
Graphic Equalizer: A device with a number of filters used to change the gain or atten-
uation of a signal at pre-selected frequencies. The bandwidths of the filters are typically
set to one- or 1/3-octave and are usually not adjustable by the end user.
Latency: The delay through a given unit or system. Latency is often referred to as the
throughput delay of a device. It is typical for digital delays to have a small latency even
when they are set to zero time delay.
Linear Scale: The term linear, refers to a set of values or scale of a graph on which
values are evenly spaced. On a linear scale, each value (or unit) has equal dimension.
Logarithmic Scale: A scale where each power of a given number (e.g., ten) is given
equal dimension.
Magnitude: A number assigned to a quantity so that it may be compared with other
quantities. For complex quantities, the magnitude is the square root of the sum of the
squares of the real and imaginary parts.
Nyquist Frequency: In digital audio, the Nyquist frequency is equal to one half of the
sampling rate. The Nyquist frequency represents the highest frequency obtainable in
digitized a signal sampled at a given sampling rate.
Octave-Band Resolution: Octave band resolution combines all data points in a given
octave and displays a total energy value for each octave band (as opposed to a linear or
logarithmic narrowband display that plots the value of individual FFT data points).
Standard octaves used in audio measurement are centered on 16, 31.5, 63, 125, 250,
500, 1 kHz, 2 kHz, 4 kHz, 8 kHz. and 16 kHz (cycles per second).
Overlap: For the purposes of Smaart 6, overlap refers to the amount of data each suc-
cessive FFT Frame shares in common with the one before. Overlapping FFT frames are
analogous to shingles on a roof. When no overlap is used, each new FFT frame begins
where the last one stopped, as beads on a string.
Parametric Equalizer: Equalizers are devices with one or more filters that affect the
frequency content of a signal. On a parametric equalizers, the parameters of the filter(s)
including gain or attenuation, frequency and bandwidth are user-adjustable.
Phase Shift: A timing difference in a signal (relative to some reference) at one or more
frequencies, typically expressed in degrees.
Pink Noise: A random (or pseudorandom) signal in which, over a given averaging
period, each Octave-band has an equal amount of energy.