Gate length standard?

Development
1

Just wondering if there is a standard in vcv for handling cv for gate length. 1v = 1second?
Suppose I have a both a cv input and a param knob for gate length.
Should cv override param? Be scaled by it?
I can come up with my own answers of course but is there a “more standard” way to handle this?
If so, could be worth adding to https://vcvrack.com/manual/VoltageStandards? Thanks

2

Pulse width? Which is usually a % or multiplier and is never less than 0.1 or greater than 0.99 otherwise there would be no pulse and it would be a steady voltage. e.g. 50% or 0.5 of 2Hz is 1Hz gate is 50:50 gateOn:gateOff

3

Hm, good thought but I’m not sure it’s suitable for my purposes.
I’m looking to generate gates from arbitrarily spaced outside triggers, rather than a steady pulse / set frequency.
so i won’t know “how long 100% is” ahead of time, so to speak.

4

99%

Can’t be 100% or 0%. It would be 99% of the trigger frequency (2Hz * 60 * 60 * 0.99) / 1000 ms = 7.128 sec

5

I use bog audio DGATE often,. seems to be a good setup. from the git; “A trigger-to-gate utility, with gate duration up to 10 seconds, and an optional pre-delay of up to 10 seconds. A trigger pulse is emitted at END when a delay/gate cycle ends. If the STOP/LOOP switch is set to LOOP, or if the trigger is high when the cycle ends, the cycle repeats.”

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6

i understand that, what i’m saying is in my case there is no steady trigger frequency.
triggers come from an external source so could happen at any time and be spaced irregularly.

7

I’ll take a look. thanks!

9

As far as i know the answer to your original question is just a flat “no”. I asume you’re looking for something like volts per octave but for gate length rather than tuning? edit to add that DGate is what I use to set gates from triggers.

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10

More broadly, is there a standard best practice for how params & inputs for the same value should interact? (input override param, input scale param)?

11

If a param has a value of [0.f, 1,f] then it would be good practice to rescale the incoming signal to the param value so the two are at the same scale. By either using rescale() or dividing the input by 10; in the case of bipolar signals this would of course be a different scale.

12

Gates turn off when they need to, e.g. user releases note, sequencer moves onto the next step, square wave generator reaches the pulse width % phase, etc. A “standard length” doesn’t make sense.

CV is additive to knobs. If you have a CV trimpot, the formula is knob + cv * trimpot.

13

I didn’t say “standard length” but “standard way of controlling length via cv” if i understand you correctly you’re saying the answer is “dont”?
I suppose that does make a certain amount of sense, if you want your notes shorter or longer than the “sequencer step” you don’t change the length of the gate, you change the decay/release on the envelope fed by the gate. do i have that right?

i see. thanks for your help.

14

I guess you can use the standard aimed at LFO & delay times : https://vcvrack.com/manual/VoltageStandards#pitch-and-frequencies

15

Quite often gate signals have durations related to the desired played note length or duration. Often though, the gate leading edge is used to trigger the ADSR which controls the note length via a VCA. But, the gate length can also directly turn the note on and off in a binary manner, rather than using an ADSR. Often sequencers provide triggers rather than or in addition to gates. The triggers are of short fixed length and just indicate the start of a note and they also drive an ADSR and VCA to shape the note lengths.