10
CV=0V generates a binary code 00000000,
CV=5V yields 10000000, and CV=+10V gener-
ates 11111111. Similarly, when offset is set
to max (for bipolar signals), an input CV=-5V
generates a binary code 00000000, CV=0V
yields 10000000, and CV=+5V generates
11111111. If your signal is hotter, it will cause
clipping in the A/D converter unless attenuat-
ed. In general, clipping is not dangerous, but
will not yield correct binary code. Use clipping
indicators in the offset slider as a guide for
optimum range settings.
The DAC section has two range options select-
ed with the slider switch. When set to high,
it can generate voltages exceeding 20Vpp.
With DAC gain set to max, a single change of
the least significant bit corresponds to 1/12V
(one semitone in the V/oct scale). Since there
are 255 steps, the voltage range is 21.25Vpp.
This is only possible if negative voltages are
allowed. For example, setting the offset slider
to minimum yields 0V at the output when the
input code is 10000000, -10.67V for 00000000,
and +10.58V when the code is 11111111.
There is nothing wrong with clipping when it
is used intentionally. For example, setting the
offset slider to max yields 0V for the input
code of 00000000 and 10.58V for input code
10000000. Higher binary numbers theoretical-
ly yield voltages that cannot be handled in Eu-
rorack; hence they are clipped. The LED in the
offset slider shaft is lit whenever the range
of -10V to +10V is exceeded. When the switch
is set to low, the DAC section halves its output
range, and the least significant bit is ignored.
In other words, a 1/12V step corresponds to
the input binary number changing by 2. There
are 127 such steps, and the voltage range is
thus 10.58Vpp which may be bipolar or unipo-
lar. For example, setting the offset slider to
minimum produces 0V at the output with the
input code 1000000x, 0000000x yields -5.33V,
and 1111111x yields 5.25V. Setting the offset
slider to max produces unipolar voltages: 0V
for code 0000000x, +5.33V for 1000000x, and
+10.58V for 1111111x. The obvious applica-
tion of these calibrated ranges is to produce
pitch voltages. However, this is not the only
use of the DAC section.
When generating audio signals with Drezno
II, you may need a lower amplitude but full
resolution (no ignored bits). In such a case, set
dac range to high, and DAC gain to a mod-
erate value. It may then be necessary to adjust
the offset slider for bipolar output.
PATCH EXAMPLES
• When used standalone (with a loop cable in-
stalled at the back), processing of signals and
voltages through ADC+DAC of Drezno II causes
only a subtle 8-bit quantization effect. Modify-
ing the binary representation creates various
discontinuities in the transfer function, depend-
ing on which bits are affected. Some radical de-
formations of a CV or audio signal are achieved
by cross-patching individual bit outputs and
bit inputs (fig. 7). Many interesting, complex
signal waveforms can be obtained by applying
this to control voltages from LFOs, envelope gen-
erators, and even sequencers.
