Expert Sleepers Disting mk4 - E-7 Euro to Buchla Converter

infinity (effectively limiting rather than compression) at fully clockwise.
Parameter 0 sets the threshold level above which compression applies (in dB).
Parameters 1 & 2 set the attack and release times. The attack time range is approximately 0.1ms-1s;
the release time range is approximately 1ms-3s.
Parameter 3 sets the make-up gain (in dB). If set to -1, the make-up gain is calculated automatically
from the threshold and compression ratio.
Parameter 4 sets a lookahead time, effectively delaying the audio slightly relative to the envelope
detection. This can be used to ensure that sharp transients are not lost during the attack time of the
envelope. The maximum lookahead is about 10ms.
Parameter 5 allows the side-chain input to be mixed into the audio output. The parameter sets the
gain in multiples of 0.5dB (i.e. the maximum is +6dB and the minimum is -40dB, which is treated
as -∞dB).
E-7 Euro to Buchla Converter
Video
X is 1V/octave input
Y is gate input
Z is tune ±0.5 octaves
A is 1.2V/octave output
B is gate/trigger output
Parameter Min Max Default Description
0 -8 8 0 Octave shift.
1 -99 99 99 Coarse.
2 -99 99 10 Fine.
3 -99 99 0 Offset.
4 0 99 49 Gate level.
This algorithm was designed for interfacing Eurorack (or more generally, any analogue synths using
the 1V/octave standard) with Buchla synths, though it has options to cater for other, non-standard
formats.
Input X/Output A convert a pitch CV from the 1V/octave standard to the 1.2V/octave standard by
default. The exact scaling is set by parameters 1 & 2:
scale = 1.0 + 0.002 * ( parameter 1 ) + 0.0002 * ( parameters 2 )
Input Y is a gate input, triggering when the level exceeds 1V. From this, a Buchla-format combined
gate & trigger is generated from output B. This is a 4ms pulse at 10V, followed by a sustained gate
at 5V.
The Z knob/CV provides a tuning control, with a range of approximately ±0.5 octaves.
Parameter 0 shifts the X input by whole octaves, equivalent to adding a whole number of Volts to
the X CV.
Parameter 3 applies an offset in mV to the A output.
Parameter 4 sets the gate level as (1+the parameter value)% of the 10V trigger pulse. The default
value of 49 therefore gives a 50% gate level i.e. 5V.
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