SPL MixDream Model 2384 16x2 Analog Summing Mixer - Manual (Page 16)

16 MixDream
Peak Limiter
The MixDream’s analog Peak Limiter protects subsequent A/D
converter stages from clipping. This limiter is based on a discrete
transistor circuitry with a musically optimized curve. Complex
program peaks can be transparently reduced by 6 dB from their
normal signal level—making a truly “fat” mix possible.
Peak Limiter Design Concept
In contrast to compressors, the MixDream limiter attenuates
peaks through an analog saturation effect similar to what occurs
in tube processors or analog tape machines. This limiter reacts
so swiftly that it can counter any problematic peak. However, its
soft-knee curve characteristics (similar to a soft-knee compres-
sor’s) simultaneously guarantee its function to be completely
transparent.
This design principle, as with any other, makes it worthwhile for
you as an engineer to be aware of the circumstances in which to
employ such a limiter. Signals that have narrow dynamic ranges
and those with fewer overtones are not effectively controlled by
limiting. In fact, in such cases it is often highly recommendable
to use simple volume controls to provide a degree of dB head-
room while retaining whatever limited dynamic differences the
signal may have.
So, where does the MixDream Limiter work most effectively? It
does so superbly with dynamic and/or summed signals such as
Drums, Synths, and so on. Similarly, its judicious “over use” can
at time provide you with interesting, useful effects, such as in
results you can obtain in an exaggerated application with guitar
or organ.
Limiter On
As with the Stereo Expander, the Pek Limiter is toggled in and
out of the chain by a hard bypass relay control switch (an illumi-
nated orange status LED indicates that the expander is active).
Control Elements
Gain Reduction
Peak Limiter
L R
Limiter On
dBu
TH
R
E
S
H
O
L
D
3
18
15
12
9
6