The 6HP wide Oakley Envelope is an easy to
use four stage envelope generator with switchable looping mode.
The ADSR is operated by a traditional gate
signal, but can also be triggered by slow rising CVs too due to
the built in schmitt trigger function. No additional ‘trig’ input
is required.
Although the panel does not imply a voltage
controlled design, the internal electronics uses a voltage
controlled slew generator at its core. This allows very fast
minimum attack and decay times. And yet, the controls with their
true exponential response, allow you to accurately adjust faster
times with ease.
Two LEDs are provided. One gives a visual
indication of the output level of the internal ADSR waveform, and
the other shows the status of the gate input lighting up when
either an active gate signal is present or the unit is in looping
mode.
Loop Modes
The Oakley Envelope incorporates a looping
mode. Looping means that the output will rise to the attack peak
at the speed determined by the attack pot and then fall to 0.5V
at the speed determined by the Decay pot. It will then rise again
to the attack peak and then fall back to 0.5V and so on.
NORM – the module behaves as a standard
ADSR.
GATED – the output will loop only when gate
is high. As soon as gate arrives the output will rise up at the
attack speed and then decay at the decay time and repeat. If the
gate is removed at any point the output will then fall at the
release time.
LOOP – The module’s output will loop
continuously in AD mode. The Gate input has no effect in Loop
mode.
In both looping modes the position of the
sustain pot can be used to turn the looping on or off. At values
above 10% the looping will stop.
Specifications:
Attack times: 0.18 milliseconds to 25
seconds (fast) or 1.4 ms to 200 seconds (slow). Charging voltage
+10V, internal attack peak +5V. Pseudo linear ramp.
Decay/Release times: 0.35 milliseconds to
30 s (fast) or 2.8 ms to 240 seconds (slow). Time measured from
90% of sustain value to 10% of sustain value. Exponential decay
slope.
Sustain levels: 0.0V to 5.0V
Current draw is approximately -22mA and +33mA.
The PCB set
The Envelope module
comprises of two printed circuit boards (PCBs) connected together
with six 0.1 (2.54mm) single in line (SIL) headers and
sockets. The main board on the rear of the module houses the
power input and conditioning, and the ADSR core. The pot board
has the pots, switch, and sockets that are attached to the front
panel, as well as the gate input, LED drivers, and output
circuitry. The main board is a four layer design, while the pot
board is a two layer design. Each board is the same size; 29 mm x
107 mm.
The
majority of the components are surface mount parts. The ICs are
SOIC, while the resistors and surface mount capacitors are 0805.
The two transistor arrays are SOT457. All components are standard
parts.
Project Downloads
Construction
Guide Our handy guide to building
Oakley DIY projects
Parts
Guide Our handy guide to buying
parts for Oakley DIY projects
Schematics are only available
to purchasers of the PCBs and will be sent via e-mail when the
boards are shipped.
Front Panel database
A Schaeffer front panel can be made for
this module. The database can be found by downloading the
following link:
6HP Eurorack format
in natural silver
To read, edit and print these
files you will need a copy of ‘Frontplatten Designer’ from Schaeffer. Panels can be ordered via the program using its
secure online ordering system.
Schaeffer are based in Berlin, Germany and
can send panels to anywhere in the world. Delivery to the UK
normally takes around ten days. For North American users you can
also order your Schaeffer panels from Front
Panel Express.
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