Junger Audio d07 - Digital Transmission Processor - Manual (Page 43)

B 2: The Jünger Audio Compresor & Expander Principle
Figure 1: Compressor characteristics
Figure 2 Expander characteristics
THE JÜNGER AUDIO COMPRESSOR &
EXPANDER PRINCIPLE
Compression is defined as the reduction of the dynamic range of the input signal
to match the dynamic range of the storage system, transmission system, and/or
the listening environment. Typical approaches to this task often result in audible
artifacts and lack luster performance. The Jünger approach takes an atypical
approach that avoids these difficulties.
In the Jünger system, compression of the program signal takes place over the
entire input level range, not just the upper end above a certain threshold level.
Compression is partly achieved by
increasing the level of low level signals.
The lower the input signal level, the
higher the additional gain applied to that
input signal by the compressor. As the
level of the input signal rises, the amount
of gain applied is reduced. Please see
the figure to the right.
Dynamic structures of the entire range of
the input signal amplitude are converted
proportionally. Even after compression
the dynamics of incoming audio are
maintained, only slightly condensed,
leaving a transparent, seemingly
uncompressed sound impression.
The gain of the compressor (called
‘range’) can be limited from 1 dB to 15dB
to prevent unacceptable increase in
back grounds during signal pauses
(e.g. ambience).
To help eliminate unwanted very low
level noise (air-conditioning, hum, and
noise), a Jünger Expander can be used.
Below an adjustable threshold level, the
expander will attenuate the level of the
incoming signal: as the incoming signal
drops so low that it is ‘in the noise‘ the
Expander reduces the signal level further
to ‘hide‘ the noise.
The Range parameter sets the maximum
attenuation applied when the incoming
signal level is within 6dB below the
Threshold level.
B
2
2.0:1
1.6:1
1.3:1
OFF
ratio
-50
-40
-30
-20
-10
[dBFS] -10 -20 -30 -40 -50 -60
output
input
range
max. 15dB
gate
OFF
6dB
-50
-40
-30
-20
-10
[dBFS] -10 -20 -30 -40 -50 -60
output
input
range
0...40 dB
threshold
level
-20...-60, off