User manual
4
frequency
shifting
The functions of these two pairs effectively
swap when the shift knob is turned to the left
of 0Hz, or a negative control voltage is applied.
Two ±5V range CV inputs are available for
modulating the amount of frequency shift:
exp fm
7
for exponential control and lin
tz fm
8
for linear control. The sensitivity
of the exponential input is switched together
with the range switch, while the sensitivity
of the linear input is controlled by the atten-
uator
9
and doesn’t change with range.
Koszalin provides several internal feedback
options. The regen switch
10
determines
internal feedback routing: from downshifted
signals, upshifted signals, or both combined
feedback amount is controlled with the re-
gen knob
11
, and CV plugged into the corre-
sponding jack
12
. The temporal character of
the feedback effect depends on the density
parameter, controlled by knob
13
and/or CV
via the corresponding input below
14
.
WHAT IS FREQUENCY SHIFTING?
Frequency shifting is a process that affects all
spectral components of a signal by changing
their frequencies by an equal number of Hz.
For example: if the input is a periodic wave-
form with a 1kHz frequency, it usually con-
tains the 1kHz component plus the harmonic
overtones: 2kHz, 3kHz, 4kHz, etc. When this
signal is shifted by 200Hz the result contains
That means the new components are no lon-
signal is inharmonic and non-periodic.
-
fect to pitch shifting, which results in scaling
the frequencies by the same factor. So, for
example, applying a factor of 1.2 would re-
sult in a signal that contains 1.2kHz, 2.4kHz,
3.6kHz, 4.8kHz, etc.—still a harmonic signal,
just with a different pitch.
Techn ically, s hi fti ng o f the spectr um i s a chieved
that is much more complex than a simple mul-
tiplication, which is sometimes inappropriately
called ring modulation.
A common fallacy says modulation is the same
as adding and subtracting signals, which is
nonsense since multiplying is not adding and
subtracting. Instead, this type of modulation
-
-
nents in such a way that their frequencies are
added and subtracted.
and offers two new signals: one with frequen-
cies shifted up and one with frequencies shift-
phase rotation, and quadrature modulations,
note:
summing both down- and upshifted signals
reduces the effect to a mere multiplication