The OUT (SOFT) output
With signal levels under 3.5V or so the soft output produces pretty much the same signal as
the main output. However, as the signal level rises on the main output, the signal seen at the
soft output becomes more and more distorted. It is effectively being gently compressed at the
top and bottom of the waveform. This is clipping of a kind since it does restrict the maximum
output voltage but because it comes in gracefully it is called soft clipping.
One can think of soft clipping as being much like ordinary audio compression but acting so
fast it it operates on each cycle of the audio waveform. The maximum signal level likely to be
seen at the soft output is not much above 6V peak.
The soft clipping output is useful to limit a CV or audio signal in a musically interesting way.
For audio it tends to bring out the fundamental tone of the signal in a subtle way. Do not
expect screaming Marshall lead tones – this is a mild effect and one that is akin to overdriving
a discrete VCA or fully open Moog ladder filter.
You can use the soft output as reasonable triangle wave to sine wave convertor. If you do this
you can also create asymmetrical distortion by using the voltage sources built into channels 3
and 4 on the Fourmix.
The output is not buffered and has an output impedance of 1K.
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