Manual
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The FXDf is a 6 Band Fixed Filter bank, oering simultaneous 6db/ Octave and 12db/ Octave inputs. The 6 lter
bands are spaced at roughly 11 to 13 semitones, covering a range of around 6 octaves. The FXDf is useful for
isolating a particular portion of the spectrum for mixing and analog or digital signal processing such as ring
modulation, amplitude modulation, pitch-shifting and reverberation. The module also has a header behind the
faceplate allowing for normalled connection of the 6 lter band outputs to the 6 inputs of RxMx allowing for
Voltage-Controlled, percussive, spectral animation. See page 4 for instructions on connecting the FXDf expansion
header to the RxMx.
In the past, the Serge System Fixed Filter used a 6db/ Octave lters, while the Moog Modular used 12db/ Octave
lters. We liked the sound of both lter slopes, so we implemented a way to use either or both simultaneously. In
this way, the FXDf also allows for blending of two audio signals. Traditionally, Fixed Filters are large modules
having 8 to 10 bands-- each with a manual level control, but rarely having any Voltage Control. The FXDf is so
small, we even had to abbreviate the words Fixed Filter! Also, by providing individual outputs, in addition to a
header for normalled connection to our RxMx 6-Channel Macro-Low Pass Gate module, Voltage Control over the
Level of each Filter band is possible through patching. We selected the 6 bands we found to produce the most
sonic energy within a typical Make Noise system patch. We also took care to space them wide enough that each of
the bands could be distinct from the others. This makes for quite an impactful sound when independently
modulating the amplitudes of the 6 bands using the RxMx or VCAs.
The FXDf contains 100% analog lters for musical applications and is not suitable for laboratory use.