Ashly Parametric Equalizers SC-63 - Manual (Page 18)

FILTER
A circuit designed to pass some frequencies, but not others. There are
three general categories of filters:
High-pass, band-pass, and low-pass.
The high-pass filter passes frequencies above a certain lim't, the low-
pass passes frequencies below a limit, and the band-pass passes one group
of frequencies without passing those above or below. Our equalizer uses
band-pass filters, crossovers use high and low-pass filters.
FREQUENCY
The repetition rate of a waveform. Frequency is measured in Hertz. One
cycle per second (cps) is one Hertz (Hz). The higher a note on a musical
scale, the higher its frequency.
FREQUENCY RESPONSE
Refers to relative gain and loss at various frequencies across the audio
band. May be illustrated by a graph called a frequency response plot,
usually graphing decibels vs. Hertz or octaves.
HERTZ (Hz)
The unit of frequency measurement,
this explains it perfectly) (Formerly called Cycles-per-Second;
HEADROOM
Refers to the increase in level above normal operating level that can be
obtained without clipping. Usually expressed in dB.
IMPEDANCE
Essentially the AC equivalent of resistance. It describes the drive
capability of an output, or the amount of drive required for an input at
any given signal level.
KHz
Kilohertz. 1,000 Hertz.
LEVEL
The magnitude of a signal, expressed in decibels or volts.
LINE LEVEL
Meaning "somewhere around OdBV" as opposed to MIC level of around -40dBV.
OCTAVE
A logarithmic unit to compare frequencies,
frequency, -1 Octave means half frequency.
+1 Octave means double
OHM
The unit of electrical resistance or impedance,
PHASE
Describes how well two signals are in step. In-phase means that positive
and negative peaks in two signals occur together, while out-of-phase
means they do not occur together. Variations in signal timing as well as
polarity can make two signals in or out of phase, or anywhere in between.
Phase is usually measured in degrees where 0 degrees is in-phase, 180
degrees is out-of-phase, and 90 degrees is in between (sometimes called
quadrature) .
PREAMPLIFIER
The first stage of amplification,
signals to line level.
designed to boost very low level
A measurement describing the sharpness or broadness of a filter.
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