Specifications

Trillium Lane Labs Plug-ins Guide12
Analog Compression
Compression is a common audio processing
technique that is essential to many recording
styles. A compressor is a specialized type of am-
plifier that acts to reduce the dynamic range be-
tween the quietest and loudest peaks of an audio
signal. When dynamic range is compressed, this
highlights quieter parts of an audio signal while
taming the loudest parts. Heavy use of compres-
sion on percussion, instruments, and vocals is a
staple in musical genres such as rock and pop.
Before the introduction of digital technology in
the studio, compressors were typically designed
around a set of analog components. Various
compressor circuit designs are known for their
distinctive sound and characteristics. Popular
analog compressors are often designed around
optical isolator, VCA (voltage controlled ampli-
fier), or FET (field effect transistor) based circuits
that produce the compression effect.
TL Aggro
TL Aggro implements a unique compressor to-
pology based on a traditional analog FET design,
with several updates for the digital age. Figure 2
shows the different modules of TL Aggro and
how they interact with the audio signal.
TL Aggro uses a reverse feedback system com-
mon to many analog compressors. In essence,
this means that the compressor is not compress-
ing the input signal but rather analyzing and
compressing the already compressed output sig-
nal. Sound weird? It is. Reverse-feedBack is a
strange and paradoxical concept. It can lead to
strange and chaotic behavior if not well-tamed.
In fact, at least one well known and popular
hardware compressor that uses a reverse feed-
Back topology becomes marginally unstable at
extreme compression settings. Despite this
sometimes unpredictable behavior, the reverse
feedBack model produces a desirable and
unique compression sound.
TL Aggro adds modern digital conveniences to
the reverse feedBack model. Precise bass com-
pensation provides for improved tracking of
bass heavy instruments or a complete stereo
mix. TL Aggro provides linked stereo operation
to preserve stereo imaging as well as full side-
chain support. A tube drive module adds addi-
tional tube-style distortion if desired.
TL Aggro uses a program dependent release
which provides more natural sounding com-
pression. In essence, the program dependent re-
lease works to slow down the release time of
compressor so that it more smoothly rides the
average loudness of the audio material.
The most unique feature of TL Aggro is its
Threshold control. Most reverse-feedBack com-
pressors do not implement a Threshold control
typical to non-FET compressors. Instead, they
provide an input control that increases the
amount of compression as the unit is driven
harder. However, an input control adjustment is
often less intuitive than a Threshold control.
Figure 2. TL Aggro signal flow, processing, and controls