7
offer the ripple waves at full amplitude,
without the decay response. The decay
curve is individually available for a and
b at the impulse outputs
23
.
mOdulAtIOn And SelF PAtchInG
Although Sofia alone can synthesize a
wide range of acoustic, woody, organic,
and animal-like, as well as high, fuzzy,
and bright sounds, it greatly benefits
from being animated through its multi-
ple CV inputs. Patching complex modu-
lations, e.g., envelopes from Xaoc Devices
Zadar, some audio signals, or even white
noise to various parameter inputs, adds a
whole new dimension to the sound.
The user is encouraged to try various
self-patches from the individual outputs
to inputs within and between elements
a and b, which sometimes transforms So-
fia into a wild and scary beast.
AcceSSOrY
Our high quality Coal Mine black panels
are available for all Xaoc Devices mod-
ules. Sold separately. Ask your favorite
retailer. •
fof
synthesis
The classic FOF synthesis technique proposed by X. Rodet in the 1980s efficiently synthe-
sizes vocal-like formants in the time domain without resorting to digital filters, which, at
the time, were expensive to implement. Rodet observed that the complex response of a
vocal tract may be decomposed to parallel acoustic resonant filters that produce decaying
sinusoidal tones (ripples) in response to each pulse of air pressure from the larynx. There
is a direct relationship between the density and decay rate of the decaying sinusoid and
the frequency position and spectral width of the formant.
1
0.5
0
-0.5
-1
0 1000 2000 3000 40000
Amplitude (V)
Time (μs)
1
-10
-20
-30
-40
0 20 30 40 60
Spectrum (dB)
Harmonic No.
