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Analog Elemental Series
DynaMaxx | Technology
Full-Band versus Multi-Band
Some compressors try to solve the problem of high frequencies being modulated by low
frequency compression by moving to a split band system, so why don‘t we do that?
Multi-band compression seems like a good idea to overcome the pumping effects caused by
heavy bass compression also causing high frequency sounds to be pulled down in level. For
example, with a regular compressor, you may be compressing a bass-drum but the release
time is set a little too long with the result that the following hi-hat gets ducked in level. Multi-
band technology splits the original signal into two or more bands to be processed individu-
ally, and in this way, heavy gain reduction at the bass end doesn’t affect the level of the high
frequencies.
Sounds like a good idea, but the elaborate level of automation and the double VCA circuitry
allow to dispense with multi-band techniques – and that provides two main advantages:
1. Neutral Sound
Multi-band technology has a significant sonic short-coming: due to different levels of
processing within the various bands, each band’s output may be changed in phase response,
so that when the bands are recombined, the signal tends to have reduced dimensions and
sounds incoherent and colored.
2. Time Saving
DynaMaxx offers simplicity of control. With Multi-band systems you have to set all the time
constants plus Gain, Threshold, and Ratio for each band. With a fully manual Four-Band-
compressor, this would mean 20 parameters to set up per channel. DynaMaxx needs 2 – and
provides better sound results.
Attack Time Automation
First it’s necessary to see what happens when a compressor is used with a fixed attack time
setting. For example, the sound of an e-bass can either come in smoothly (especially with
fretless basses), or with a very fast transient attack when slapping. If the attack time is set to
minimum (very short), the compressor is able to catch the peak of the transient attack but any
following notes will suffer increased transient distortion because the control voltage within
the compressor rises further as successive notes are processed. This behavior is sometimes
described as ‘surfing’, and can be overcome by setting a lightly longer attack time, but now
some peaks get through because they are faster than the compressor’s attack time. Including
a separate Peak-Limiter to catch those fast transients has disadvantages: if this is done using
two VCA stages, the signal undergoes more quality degradation than is desirable, but even
with designs that use the same VCA for both compression and limiting, you still end up with
more controls than necessary.
The DynaMaxx doesn’t need a separate peak limiter, because it detects and controls very fast
transients automatically. Processing is so fast that all signals stay within the soft-knee curve
for a more natural sound.
The attack time can be reduced in the instant of a percussive hit or bass guitar slap to a
minimum of 50 microseconds. As soon as the peak is passed, the attack returns to a longer
time constant (up to 10ms of first Attack time circuitry), and in this way, both pumping and
distortion are avoided.
The ability of DynaMaxx to respond so quickly is clearly valuable when complex stereo mixes
are being treated. If, for example, a snare drum peak occurs, DynaMaxx rapidly changes to a
very short attack time so that the snare hit keeps its original transient characteristics rather
than sounding ‘softened’. Following signals are compressed using longer attack times imme-
diately.
The DynaMaxx uses 12dB/octave filtering instead of the 6dB/octave filtering used in stan-
dard compressor side-chains so as to increase the precision and speed of transient detection
and processing. The signal-dependent adjustment of the attack time parameter is too fast
to be audible. If the DynaMaxx is operated in its normal compression mode, breathing and
pumping effects are avoided.