Module CV input fail safe / voltage limit


(Latif) #1

I been wondering for a while whether to start a conversation about this or not.
So here goes , it might seem redundant for the more seasoned users of any modular setup.
But for people like me that are getting more into the technical side of this since a couple of years,
some things aren’t always clear and result in user error.
Luckily in this virtual environment the damage doesn’t result in a fried rack module.

Sometimes i am able to crash VCV,
(possible better term is: the module inside VCV is crashing, causing VCV to crash).
My guess is this happens when a voltage goes way to far on a CV input.

For example one of the last occasions where i had this happen, is on the Resonator - Audible Instruments,
cv input for Frequency attenuator. I was able to reproduce this several times.

When i read the specs for MI - Rings, it says: CV inputs: 100k impedance, +/- 8V.
After using volt meter in Rack, i see that the voltage i was sending from a SH could peak at 12.5 volt.
Might this crash the module in VCV, or is this not possible?

If so, wouldn’t it be an idea (don’t know if this makes any sense, or technically possible),
that a module was designed so it would only accept the voltage that is within it’s design specs, and ignore anything above or under?


(David O'Rourke) #2

It is recommended that module developers limit the input voltages if an out of limit voltage would cause a problem, and many of them do.

As to whether that causes the crash you are seeing, I wouldn’t know.


(Andrew Belt) #3

No need to have an introduction speech, just report the bug on GitHub.


(Latif) #4

@Vortico
well i don’t know whether it is a bug or my own wrong doing, hence the “introduction speech” as you call it.

if you are trying to say that it is already the case that cv inputs have fixed limit value, then please do state so.
so that i understand that it might be a bug that i see happen.


(Andrew Belt) #5

If anything crashes Rack, it is certainly a bug.


(Patman / NYSTHI Manual) #6

And to extend on that, even if an initial bug report on rack proper is closed due to it being an issue specifically caused by a module within a plugin, it can be crossreferenced on Github, so you’re not wasting your time.


(Patman / NYSTHI Manual) #7

Something somehting XY Problem?

here’s a reference on voltage standards within Rack

https://vcvrack.com/manual/VoltageStandards.html


(Latif) #8

Fair enough