49
Topics in this section include:
Limiters
Overview
Limiters prevent clipping by attenuating
signals that exceed a set threshold. The
amount of attenuation is defined by the
ratio of the limiter and expressed as two
numbers.
The time it takes for limiting to begin
once signal has exceeded the threshold
is referred to as the attack time, and
the time it takes for limiting to cease
once signal has fallen back below the
threshold is referred to as release time.
Sound Devices recommends using limiters at all times. Without input limiters,
high signal conditions can overload a channel and cause distortion. In normal
operation, with a properly set gain structure, the threshold of the input limiter
is rarely reached. The default threshold of all input limiters on the 664 is 16 dBu
(4 dBu below clipping).
All 664 limiters use a 20:1 compression ratio. This means that any signal that
exceeds the threshold by 20 dB will exit the limiting stage at only 1 dB above
the threshold. The 664 limiters have a 1 ms attack time and a 500 ms release
time.
The input limiter is actively limiting when the respective input’s Input Activity
LED illuminates yellow. Limiting activity will also be displayed as a yellow square
on the right side of the input’s meter on the Main screen. If the limiting activity
is regularly indicated, reduce the amount of gain applied to the channel by turn
-
ing down the Trim control.
Summary of Contents for 664
Page 1: ... 664 Field Production Mixer with Integrated Recorder User Guide ...
Page 4: ...User Guide 4 ...
Page 20: ...User Guide 20 ...
Page 48: ...User Guide 48 ...
Page 60: ...User Guide 60 ...
Page 68: ...User Guide 68 ...
Page 76: ...User Guide 76 ...
Page 88: ...User Guide 88 ...
Page 108: ...User Guide 108 ...
Page 112: ...User Guide 112 ...
Page 118: ...User Guide 118 Status Bar Viewing Area Tab Bar ...
Page 140: ...User Guide 140 ...
Page 146: ...User Guide 146 ...
Page 174: ...User Guide 174 ...
Page 180: ...CS 688 180 ...