QM
1000P
User Manual
User Manual
Q Motion Series
QM 1000P
10
Glossary
Basic professional audio practice and hints for best
results .
PRE-AMPLIFIER: A part of the signal chain where
a signal from a microphone, turntable, CD player
or other source is first amplified . This will normally
be at the input of a mixer . The pre-amplifier is
necessary to boost the signal enough to be then
mixed and amplified by a power amplifier .
POWER AMPLIFIER: Boosts the signal enough so it
can be reproduced by a loudspeaker .
ELECTRONIC CROSS OVER: Splits the full range
audio signal to separate high and low frequencies .
This is done to send low frequencies to the bass
speaker and high frequencies to the tweeter or
high frequency horn driver .
SELF-POWERED: Refers to a speaker or a
mixer that contains a power amplifier .
CLIPPING: Distortion that is caused by having too
much signal at an input causing the amplifier to
overload . It is called clipping because it will cause a
smooth wave to be cut off at the peak of the wave .
In other words, “clipped” .
GAIN STRUCTURE: The relationship of input levels
to output levels in a signal chain . An example of
incorrect gain structure is when a mixer is turned
up to the point of audible distortion (red lights
flashing and signal overload), while the power
amplifiers are turned down and running at only
30% power .
COMPRESSION:
A process that reduces the dynamic
range of signal . In other words, the loud parts of a
signal are decreased while the quiet parts appear
louder . When used correctly, compression can
make live music sound more even and balanced .
LIMITER: An electronic device that will prevent
the signal from exceeding a set level of output .
Normally used as a system protection to prevent
signal from being over driven by excessive input .
PHASE (IN or OUT OF PHASE):
This really means
speaker polarity . The input terminals of a normal
loudspeaker have a + positive red terminal and
a - negative black terminal . In the case where there
are two speakers operating as a pair or together
as an array, the wiring must be the same from one
speaker to the next . If a speaker connector, speaker
lead or speaker box is wired in reverse to a box near
it, loss of performance will result . This may be in the
form of lost low frequency response . In this case
you will see the bass speaker working hard but as
you move away from the box, the bass frequencies
will seem to “disappear” .
Check that your speaker leads do not
have one lead wired in reverse at one end
and that the speaker boxes are all wired
correctly internally . This can happen when
a speaker box has been repaired and then
not assembled with the wiring connected
correctly .
Clipping
Clipping
Compressor
Threshold
1:1
3:1
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10
10
Limiter
Threshold
O
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10
10
1:1
0:1
