46
A secondary advantage to this arrangement is that the MIDImplant’s CV1 output is still available at
the
panel when bypassed at the KBD CV Out jack. If you have a 1601 sequencer, you can use the CV1 signal
to transpose the sequencer by patching it to the CV Input on the 1601. This inserts the 1601 between the
MIDImplant and the TTSH, for creating arpeggios.
Configuration and calibration of the MIDImplant is covered in the calibration sections, above.
Some observations about MIDImplant
1.
Make note of all Sysex commands you apply to program your MIDImplant. You may need to run
them again in the future.
2.
In the above configuration, the modulation wheel CV is made available. To use this in the
traditional sense, make use of the Ring Modulator as a second VCA. Set the Ring Modulator mode
to DC, set VCO2 to LFO mode, connect the sine or triangle output of VCO 2 to the left input of the
Ring Modulator and the MIDImplant CV2 output to the right input. Raise the sliders to taste. The
Ring Modulator output can now be used to modulate the VCO pitch, VCF cutoff, or VCA, under
control of the modulation wheel, for vibrato or tremolo effects.
3.
The option for MIDI through is not compliant with the MIDI specification for through, and off
board components, including a reg5V source, are needed to complete this quasi-thorough
function. See the MIDImplant documentation, or just skip implementing the through port.
4.
The Learn function, using a momentary switch, provides some rudimentary programming
capability, if you don’t mind flying blind. Sysex is really the way to go with programming, however.
MODIFICATION: IMPROVING CALIBRATION ACCURACY
Bourns makes four-turn trimmers that fit the existing trimmer footprints. They are costly, about $6US at
the time of this writing. These are not included in the Synthcube kit or BOM. You may install these in the
VCO trimmer locations for Frequency and 1V/Octave calibration, to improve precision. Keep in mind that
these merely introduce a gear between the adjustment screw and the resistive element. The resistive
element is the same. You don’t really get four times the
accuracy, but it is still a significant improvement.
The parts are:
•
Bourns 3339P-1-253LF (qty:3)
•
Bourns 3339P-1-104LF (qty:3)
MODIFICATION: INCREASE ADJUSTMENT RANGE: LEDS
The standard adjustment range for the LED trimmer does not allow for extinguishing the LEDs. The range
may be expanded, without affecting overall brightness, to allow adjustment all they way to off. Replace
LED-R1 (3k3) in the main LED driver section with a wire jumper.
MODIFICATION: REVERB IMPROVEMENTS
Improvements to the reverb system fall into two general categories: changing the character of the spring
unit, and improving the overall noise rejection.
Substitution