FBK IN socket then only the delayed version of this signal will heard at both the DLY OUT
and MIX OUT sockets.
When the FBK switch is in POS it has no effect on the signal passing into the FBK IN socket.
In NEG mode the module inverts the signal so the audio going into the delay circuitry is now
completely out of phase with the FBK IN input signal.
With no jack plug inserted into the FBK IN socket the delayed audio signal is automatically
passed to the feedback control pot. When the control pot is at its minimum then no signal is
passed from the delay output back into the input. In this case the position of the feedback
switch has no effect as there is no signal to invert.
At high levels of feedback the module may self-oscillate – although this will depend on how
the unit has been calibrated. The frequency of self-oscillation will depend on a variety of things
but the key factor is the delay time. Feedback is stronger at longer delay times, that is, when
the delay control pot is at its lowest settings. It also slightly stronger when the FBK switch is
in NEG mode. If the unit has been calibrated to self-oscillate then self-oscillation will happen
more readily in NEG mode and at longer delay times. The output signal level at high feedback
levels can get very loud and be somewhat unpredictable.
For the classic flanger sounds both switches would normally be set to the same mode.
The Drive Control
Whilst having dedicated input level and output level controls is more common in rack effects
the Oakley Flanger features a single Drive control. This combines the actions of both the input
and output level controls in one control. Turning up the Drive increases the signal level sent to
the BBD devices, while at the same time reducing the signal level from the BBD devices. This
way input sensitivity can be increased without any change in output level. This is very useful
when using the Flanger module to process external instruments or indeed the wildly varying
signal levels of a modular.
For clean signal processing the green LED should be mostly lit and the red LED lit only very
occasionally. Allowing the red LED to activate shows that the signal is now being overdriven
producing a more distorted sound. If the red is lit even with the Drive pot at its minimum this
indicates that the input signal level is too large. This will not damage the unit but you should
either turn down the signal level via the sending instrument's volume control or use another
module (like the Oakley Multimix) to attenuate the signal a little.
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