Mode 5: True chorus with 10 chorus members, each having a
maximum of 8 harmonics. Also the possibility to generate non-
harmonic overtones.
Mode 5 generates 10 different fundamental frequencies, each with a maximum 8 harmonics. The fundamental
frequencies are generated close to each other, therefore making a true chorus of 10 members ("true" used here to
emphasize the difference from typical chorus effects that loop the same voice to create a similar effect). The
difference of the frequency of the individual voices can be adjusted using
adjust 1
, and also modulated using an
envelope connected to
modulation 1
. The maximum deviation of the chorus voices from the nominal note
frequency is a little more than +- one full note. All the 10 voices will be inside this range, with approximately equal
distances. At reset all voices are at the nominal note, and you need to turn
adjust 1
CW to increase the deviation,
with some envelope or
D.C. out
connected to
modulation 1
.
The spectra of the chorus voices can be adjusted and modulated in the same way as in Mode 0, i.e. using sliders 1 -
8 and their linked
envelope inputs
. All the voices have identical spectra (save the fact that all the harmonic
frequencies follow the same relative frequency shift as their fundamentals).
The last 8 sliders from 9 to 16 are used to control the relative amplitudes of the chorus members, in the logical order
from the lowest to the highest. Note that these can also be modulated in the same way as harmonics, i.e. by linking
the sliders 9 -16 to some of the
envelope inputs
1 – 4 through the virtual switchboard. Figure 3 shows an example
with 10 chorus members, each having just 3 harmonics.
This mode also has the possibility to adjust the harmonics outside of harmony by turning
adjust 2
CW. The whole
group of 10 overtones will be shifted equally. The direction of shift is always towards higher frequencies from the
nominal harmonic frequency, up to 1.8 times the nominal frequency. This adjustment can be used to generate voices
that resemble natural non-harmonic voices, like bells or drums with proper envelope shaping of amplitudes. The
adjustment using
adjust 2
advances stepwise, generating audible clicks, therefore not useful during live
performance.
A drawback from the true chorus operation is that such close frequencies inevitably will interfere, i.e. make beating
effects with their periods varying inversely proportionally to the frequency difference. If the amplitudes are
identical, there will be periodically almost complete cancellation and full double amplification of the beating
harmonic (note that they occur at different fundamental frequencies for different harmonics). For avoiding the full
cancellation, it may be useful to use different amplitudes for the chorus members by adjusting sliders 9 - 16, and
when both the deviation and the individual amplitudes are modulated dynamically, the beating will not be periodic
and not so disturbing. If acceptable, also slight shifting of the overtones out of harmony can be used for adjustment.
As a summary, here is a list of the patch cable connections and adjustments:
1. Connect envelope generator outputs to all those of the
envelope inputs
that you have activated for the
desired harmonic sliders 1 - 8. Remember that on power up, all are connected to input 1.
2. Correspondingly, Connect envelope generator outputs to to all those of the
envelope inputs
you have
activated for the desired harmonic sliders 9 - 16 to control the chorus member amplitudes. If you want
to keep the member amplitudes constant, connect the selected
envelope inputs D.C. Out
.
3. Connect an envelope output to
modulation 1
if you
want to modulate the frequency deviation of the
chorus. Otherwise connect
D.C. Out
to
modulation 1
to
keep the deviation constant. With no signal at
modulation 1
there is no chorus.
4. Connect the note determining control voltage to the
CV note
input and the gate trigger signal to the
gate
input, and optionally connect the
CV pitch
and
CV velocity
inputs to the corresponding MIDI
input module outputs.
–
Set the chorus member spectra by sliders 1-8 (all members have identical spectra) and relative chorus
member amplitudes using sliders 9 -16. Note that slider 9 controls three chorus members, while the rest 10
– 16 each control a single member.
–
Use
adjust 1
to control the sensitivity to the signal at
modulation 1
.
–
Use
adjust 2
to shift the overtones out of harmony, if desired.
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