AAS ULTRA ANALOG VA-3, Руководство пользователя

Страница: 45 / 88

5.3 The Synth View 45
Filter Drive
As seen in the preceding sections, some filters can boost the signal in some regions of the spectrum.
Theoretically, with a high Q-factor the amplification can reach up to 50dB, but in real life, electronic
components saturate before this level is reached and saturation is introduced in the signal. In other
words, the output signal of a circuit can raise linearly up to a certain value but then begins to raise
more slowly up to a value where the output is clipped to the maximum output value allowed by the
circuit. This effect is typical of the sound signature of vintage circuits and is implemented in
Ultra
Analog VA-3 through the Drive control as shown in Figure 27. There are 6 different saturation
patterns implemented, the three first being symmetrical, meaning that the saturation is the same
for positive and negative values of the signal while for the three remaining the distortion pattern
applied is not the same for positive and negative values of the signal.
Figure 27: Saturation curves of the resonant filters. For asymmetrical curves, the saturation level
and threshold are different for positive and negative values of the input level.
The distortion algorithms are selected with the Drive drop-down menu and are numbered from
one to three for both symmetrical and asymmetrical saturation. These distortion algorithms range
from very low distortion (clean circuit) to very high distortion.
Slave Filter 2
The Filter 2 module can be enslaved to the Filter 1 module. This can be done by clicking the
Slave toggle switch on the
Filter 2
module. In this mode, the frequency of the
Filter 2
module
follows exactly that of the Filter 1 module. The Frequency knob on the Filter2 module is then used
to adjust the offset frequency between the Filter 1 and Filter 2 modules. When slaved, the cutoff
frequency of
Filter 2
module follows exactly that of the
Filter 1
module including the effects of the
modulation signals from the keyboard, LFO or envelope generator acting on the Filter 1 module.