Connections and controls in detail
The group of four
envelope input
jacks need to be connected to envelope generator outputs.
They tolerate positive
voltage from 0 to a maximum of +8 V. In most operating modes the full scale is reached with a 6 V input, and
higher voltages will saturate. Their input impedance is 10 000 Ohms, therefore a typical envelope generator can
easily drive several inputs simultaneously.
Mainly for testing purposes, HG-16 has one constant voltage output labeled
D.C. out
that can be connected to the
envelope
or
modulation
inputs.
It allows playing the unit even without any external envelope generators. However,
this means that you have a constant envelope for all the sounds or minimum attack/release duration if the gate signal
is switched on.
In most operating modes the minimum requirement is to connect one envelope generator output to input no. 1. but
the full functionality of HG-16 calls for several independent generators. Virtual switchboard circuitry is provided. It
routes the envelopes to control different features in the synthesizer: see the later section “Virtual switchboard” for
its instructions.
In the front panel there are also two additional inputs
modulation1/2
with the same input characteristics as the
envelope inputs. They are used for various external modulation inputs, and typically also require external envelope
outputs to be connected, see their specific use in detail in each of the operating mode instructions.
When connecting patch cables between the inputs and outputs, be careful to always plug the wire first to the inputs,
and only after that to the outputs. This is to prevent accidentally shorting the hot plug end to the grounded metal
surfaces. It is especially important when using the
D.C. out
-terminal which has a low output impedance of 130
ohms.
The remaining connectors and controls in the
front panel
are the following:
–
volume
, a typical output volume potentiometer.
–
adjust 1
and
adjust 2
are multiturn rotary knobs that have control functions specific to each operating mode.
–
Three position toggle switch
gate on/off/envelope select
. The HG-16 black assumes that the modular
synthesizer gate signal is connected through front panel plug (contrary to the original HG-16 that had it bus
connected). In typical Eurorack systems the gate signal controls note activation and e.g. external envelope
triggering. However, because the HG-16 relies on external envelopes and an external note determining VC
input, it can be played both gate connected and disconnected from the bus. The unconnected state (toggle
switch center, or “off” position) is mostly preferred, because then you can also utilize the envelope generator
release functionality (i.e. when the gate signal would otherwise terminate the note). The operating modes 7, 9
and 12, however, require the gate to be connected, so the toggle switch has to be in the “on” position in these
modes. The third position of the toggle switch, “envelope select” is described in the section on the virtual
switchboard.
–
16 optical slider potentiometers. As expected, they are used for setting the amplitude of the 16 harmonics in the
basic mode, however, in the various operating modes, they may have other uses, see the mode documentations.
–
Finally, the
mode select
rotary selector is used for selecting one of the 14 possible operating modes of the
synthesizer. Note that modes over 9 have the led “+10” illuminated.
NOTE
: rotate the selector rapidly from 9 to 0 or from 0 to 9, otherwise intermediate spurious switch states
prevent moving to or from the states over or under 10. However, stay at least 1 second at 9 or 0 before the +10
border crossing
, because the selector has a rather slow debounce filter.
In addition to the front panel controls, there are also three ground lift switches at the
backside
: They can be found at
a larger opening in the steel grille, at the top of the enclosure. See their use in the section “Grounding and
shielding”.
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